Syslog Message Reference — One Sample per Event Type

This page lists a sample Syslog message for every event type MDSS can emit to an external logger. Use it to build parsers, field extractions and detection rules without having to generate each event first.

MDSS emits 98 distinct event types across 12 categories. Each is listed below with its LogType value, the fields it carries, and a complete sample message.

For how to configure a Syslog destination, see External Loggers — Streaming the MDSS Audit Trail to a SIEM.


1. Message anatomy

Every message is a standard RFC 5424 line with five parts:

<110>1 2026-08-13T12:15:42.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta ...] Message text └─┬─┘│ └───────────────┬──────────────┘ └─────┬────┘ └───────────┬──────────┘ └─┬─┘ │ └───┬──┘ └────┬─────┘ │ │ │ │ │ │ │ │ │ PRI │ timestamp hostname app-name proc-id │ structured message version msg-id data

Part

Notes

PRI

facility × 8 + severity. With the default LogAudit facility (13): 110 for informational, 108 for warning, 107 for error. Change the facility in the destination configuration and every PRI shifts accordingly.

Timestamp

Local time of the MDSS host, with UTC offset.

Hostname

The MDSS host that emitted the event.

App-name

Always MetaDefenderStorageSecurity.

Proc-id

Process id of the MDSS logging service. Not stable across restarts.

Msg-id

Always - (not used).

Structured data

A single [meta ...] element containing every field as a quoted key–value pair.

Message

Human-readable text. Field values are substituted inline.

What is inside [meta ...]

Two groups of fields, in one element:

  1. Message fields — one pair for every placeholder in the message text. These vary by event type and are listed per event below.

  2. Envelope fields — present on every event: TenantId, UserName, UserId, EventTimestamp, Category, LogType, Namespace, Id.

Key on names, not position

Field order inside [meta ...] is not part of the contract and may change between releases. Always parse by key name. Likewise, treat message fields as optional — the same event type carries different fields depending on what MDSS knows at the time.

Two conventions to note

All values are quoted strings. RFC 5424 structured data has no types, so fileSize="48213" is a string even though it is a number. Cast in your parser.

String values are quoted in the message text too. The message reads ... fileName: "invoice.docx" ..., with the quotes present. Numeric values appear unquoted. This affects regular expressions written against the message body — prefer the structured data.

A complete example

The most detailed event in the product, with nothing elided — a blocked file, LogType 1:

<110>1 2026-08-13T12:15:42.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" dataId="bzIxMDgwOU5xTFZ2b2E" sha256="e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855" result="Blocked" blockedReason="Infected" numberOfInfectedEngines="3" AVCount="32" threatFound="Ahnlab: Trojan/Win32.Agent" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" Workflow="Default workflow" TenantId="default" UserName="system" UserId="system" EventTimestamp="2026-08-13 10:15:42" Category="0" LogType="1" Namespace="ExternalLogger" Id="0199c0de-7a1e-7000-8000-000000000001"] File (fileName: "invoice.docx"; filePath: "/finance/2026/invoice.docx"; fileHash: "5d41402abc4b2a76b9719d911017c592"; fileSize: 48213; fileId: "0199c0de-7a1e-7000-8000-0000000000ab"; dataId: "bzIxMDgwOU5xTFZ2b2E"; sha256:"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"; result: "Blocked"; blockedReason: "Infected"; numberOfInfectedEngines: 3; AVCount: 32; threatFound:"Ahnlab: Trojan/Win32.Agent") from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") was successfully scanned by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process") with the following configuration "Default workflow".

For readability, the samples in sections 3 to 14 show the message text and the message fields, with the eight envelope fields abbreviated to <envelope>. Substitute the envelope from the example above; only Category, LogType, UserName and UserId change between event types, and those are stated in each entry.

Sample environment

All samples use one consistent fictional deployment:

Item

Value

Host

mdss-prod-01

Administrator

John Davis (jdavis), id e69e8c2d-4dcc-4489-8f40-0df84199de52

Storage

Finance-SMB, id 7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73, SMB file share

Scan

Nightly Finance, id e1b6d842-0f37-4c9b-8a15-63d0947fe2ba, scheduled

Workflow

Default workflow, id 9d4e1f60-3a72-4b85-8c19-f2073be5a1c8

File

invoice.docx at /finance/2026/invoice.docx

Tenant

default


2. Reading the actor fields

UserName and UserId identify who caused the event.

  • For an administrator action, both carry that account's values — UserName="jdavis".

  • For anything MDSS does on its own — discovery, scanning, remediation, notification delivery — both carry the literal string system.

This is the fastest way to separate operator activity from automated processing: filter on UserName="system".


3. Category 0 — Scan activities

Category="0". File discovery and scanning, scan process lifecycle, and scan and schedule configuration changes.

LogType 0 — File discovered

A file was found in storage and registered. UserName="system".

Message fields: fileName, filePath, fileHash, fileSize, fileId, lastModified, storageName, storageType, storageId, scanId, scanName, scanType.

<110>1 2026-08-13T12:15:42.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="0" LogType="0" UserName="system">] File(fileName: "invoice.docx"; filePath: "/finance/2026/invoice.docx"; fileHash: "5d41402abc4b2a76b9719d911017c592"; fileSize: 48213; fileId: "0199c0de-7a1e-7000-8000-0000000000ab"; lastModified: 08/12/2026 16:40:11) from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") was discovered by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process")

Real-time variant. When the scan is real-time, the message gains a discovery mode and a HandlingType field:

... was discovered by scan (ID: "5a20c7e9-8b41-4f63-9d28-1e7c05ab3f94", name: "Real Time Process", type: "Real Time Process") (Discovery mode: "EventBased")

LogType 1 — File scanned

The verdict for a file. UserName="system". See the complete example in section 1.

Field composition depends on the outcome:

Outcome

Message fields

Allowed

fileName, filePath, fileHash, sha256, fileSize, fileId, dataId, result, AVCount, plus storage, scan and Workflow

Blocked

The above plus blockedReason, numberOfInfectedEngines, threatFound

Not yet scanned

Identity only — fileName, filePath, fileHash, fileSize, fileId, lastModified

Allowed file:

<110>1 2026-08-13T12:15:44.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta fileName="policy.pdf" filePath="/finance/2026/policy.pdf" fileHash="8b1a9953c4611296a827abf8c47804d7" sha256="9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08" fileSize="120344" fileId="0199c0de-7a1e-7000-8000-0000000000ac" dataId="bzIxMDgwOVJrTXBXcWI" result="Allowed" AVCount="32" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" Workflow="Default workflow" <envelope Category="0" LogType="1" UserName="system">] File (fileName: "policy.pdf"; filePath: "/finance/2026/policy.pdf"; fileHash: "8b1a9953c4611296a827abf8c47804d7"; sha256:"9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08"; fileSize: 120344; fileId: "0199c0de-7a1e-7000-8000-0000000000ac"; dataId: "bzIxMDgwOVJrTXBXcWI"; result: "Allowed"; AVCount: 32 ) from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") was successfully scanned by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process") with the following configuration "Default workflow".

Scan failure — emitted at error severity, PRI <107>, with a different message and no verdict fields:

<107>1 2026-08-13T12:15:46.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta fileName="archive.zip" filePath="/finance/2026/archive.zip" fileHash="c4ca4238a0b923820dcc509a6f75849b" fileSize="9812443" fileId="0199c0de-7a1e-7000-8000-0000000000ad" lastModified="08/12/2026 09:02:55" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="0" LogType="1" UserName="system">] Unable to scan file (fileName: "archive.zip"; filePath: "/finance/2026/archive.zip"; fileHash: "c4ca4238a0b923820dcc509a6f75849b"; fileSize: 9812443; fileId: "0199c0de-7a1e-7000-8000-0000000000ad"; lastModified: 08/12/2026 09:02:55) from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process")

Scanned with identity. When MDSS reuses a previous result instead of rescanning, the text reads was successfully scanned with identity in place of was successfully scanned.

File version variant. On storages that keep versions, the label becomes File version and the fields are fileVersionName, fileId, fileVersionPath, fileVersionHash, fileVersionSize, fileVersionId, createdAt.

LogType 2 — File discovery failed

Discovery could not complete for one file. Emitted at error severity, PRI <107>. UserName="system".

Message fields: ObjectId, objectPath, storage, scan, FailureReason.

<107>1 2026-08-13T12:15:48.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta ObjectId="0199c0de-7a1e-7000-8000-0000000000ae" objectPath="/finance/2026/locked.xlsx" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" FailureReason="Access denied" <envelope Category="0" LogType="2" UserName="system">] Unable to discover file with ID "0199c0de-7a1e-7000-8000-0000000000ae" with path "/finance/2026/locked.xlsx" from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process"). Reason: "Access denied"

File skipped uses this same event type

When a file is skipped rather than failed — excluded by a filter, for example — MDSS emits LogType="2" at warning severity, PRI <108>, with the same message shape and the skip reason in FailureReason. Distinguish the two by severity, not by event type.

LogType 3 — File cancelled

A user cancelled processing for a file. Carries that user's identity, not system.

Message fields: file identity fields.

<110>1 2026-08-13T12:16:02.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" <envelope Category="0" LogType="3" UserName="jdavis">] File (fileName: "invoice.docx"; filePath: "/finance/2026/invoice.docx"; fileHash: "5d41402abc4b2a76b9719d911017c592"; fileSize: 48213; fileId: "0199c0de-7a1e-7000-8000-0000000000ab"; lastModified: 08/12/2026 16:40:11) has been cancelled

LogType 100 to 103 — Scan process lifecycle

One event per scan run and storage. UserName="system". The ScanType field holds the lifecycle action, lower-cased.

LogType

Action

Severity

100

started

informational, <110>

101

completed

informational, <110>

102

cancelled

informational, <110>

103

failed

error, <107>

<110>1 2026-08-13T12:15:40.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" ScanType="started" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" <envelope Category="0" LogType="100" UserName="system">] Scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process") "started" for storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73")

Substitute ScanType="completed" with LogType="101", ScanType="cancelled" with LogType="102", and ScanType="failed" with LogType="103" and PRI <107>.

Two fields named for the scan type

scanType (lower case s) is the kind of scan — Scheduled Process, Real Time Process or Instant Process. ScanType (upper case S) is the lifecycle action on these four event types. They are different fields.

LogType 1500 to 1503 — Scan configuration changed

An administrator added, updated, deleted or imported a scan.

LogType

Action

1500

added

1501

updated

1502

deleted

1503

imported

Message fields: Scan, Type, Action, User. Add and update also carry WorkflowName, UserAgent, WorkflowRule, ScanPoolName, ScanInstances. Add, update and delete also carry the storage fields.

<110>1 2026-08-13T09:22:10.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Scan="Nightly Finance" Type="Scheduled" Action="added" User="jdavis" WorkflowName="Default workflow" UserAgent="" WorkflowRule="" ScanPoolName="Primary pool" ScanInstances="https://core-01:8008" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" <envelope Category="0" LogType="1500" UserName="jdavis">] Scan "Nightly Finance", type: "Scheduled" was "added" by "jdavis". Workflow: name - "Default workflow", user agent - "", workflow rule - "". Scan pool: name - "Primary pool", scan instances - "https://core-01:8008". Storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73")

Failure variant — error severity, PRI <107>, fields User, Action, Scan, ResponseMessage:

<107>1 2026-08-13T09:22:12.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta User="jdavis" Action="add" Scan="Nightly Finance" ResponseMessage="A scan with this name already exists" <envelope Category="0" LogType="1500" UserName="jdavis">] User "jdavis" was unable to "add" scan "Nightly Finance". Response message: "A scan with this name already exists".

LogType 1900 to 1904 — Scan schedule changed

LogType

Action

1900

added

1901

updated

1902

deleted

1903

imported

1904

skipped

Message fields: scanName, scanId, Action, User, storage fields, WorkflowId, WorkflowName.

<110>1 2026-08-13T09:25:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta scanName="Nightly Finance" scanId="b83f27a5-14c9-4e06-9f7b-2d58e0ca934f" Action="added" User="jdavis" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" WorkflowId="9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" WorkflowName="Default workflow" <envelope Category="0" LogType="1900" UserName="jdavis">] Scan schedule (Name: "Nightly Finance"; ID: "b83f27a5-14c9-4e06-9f7b-2d58e0ca934f";) was "added" by "jdavis" for storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") with Workflow (Id: "9d4e1f60-3a72-4b85-8c19-f2073be5a1c8"; Name: "Default workflow")

LogType="1904" uses Action="skipped" and is emitted by the system when a scheduled run is skipped, so UserName="system".

Failure variant — error severity, PRI <107>:

<107>1 2026-08-13T09:25:04.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta User="jdavis" Action="add" scanName="Nightly Finance" scanId="b83f27a5-14c9-4e06-9f7b-2d58e0ca934f" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" <envelope Category="0" LogType="1900" UserName="jdavis">] User "jdavis" was unable to "add" scan schedule (Name: "Nightly Finance"; ID: "b83f27a5-14c9-4e06-9f7b-2d58e0ca934f";) (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73")

4. Category 1 — Post actions

Category="1". What MDSS did about each file after scanning. All are emitted by the system, so UserName="system".

Every post-action event shares one message shape:

{PostAction} applied to file {file fields} from storage {storage fields} by scan {scan fields}. {outcome sentence}

PostAction holds one of: Tagging, Blocked file remediation, Allowed file remediation, Discovered file remediation, Scan file versions.

LogType 200 — File tagged

Message fields: PostAction, file identity, storage, scan.

<110>1 2026-08-13T12:15:50.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta PostAction="Tagging" fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="1" LogType="200" UserName="system">] "Tagging" applied to file (fileName: "invoice.docx"; filePath: "/finance/2026/invoice.docx"; fileHash: "5d41402abc4b2a76b9719d911017c592"; fileSize: 48213; fileId: "0199c0de-7a1e-7000-8000-0000000000ab"; lastModified: 08/12/2026 16:40:11) from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process").

LogType 205 — Blocked file moved

Move and copy actions add three destination fields: destinationStorageName, destinationStorageType, destinationStorageId, and RelativeObjectName for the path written at the destination.

<110>1 2026-08-13T12:15:52.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta PostAction="Blocked file remediation" fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" destinationStorageName="Quarantine-SMB" destinationStorageType="Category: FileShare, Protocol: Smb, Vendor: Generic" destinationStorageId="2c94f0b7-6d13-4e8a-b5f2-90a7cd31e648" RelativeObjectName="/quarantine/2026-08-13/invoice.docx" <envelope Category="1" LogType="205" UserName="system">] "Blocked file remediation" applied to file (fileName: "invoice.docx"; filePath: "/finance/2026/invoice.docx"; fileHash: "5d41402abc4b2a76b9719d911017c592"; fileSize: 48213; fileId: "0199c0de-7a1e-7000-8000-0000000000ab"; lastModified: 08/12/2026 16:40:11) from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process"). The blocked file was moved to storage (name: "Quarantine-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "2c94f0b7-6d13-4e8a-b5f2-90a7cd31e648") Destination objectPath: "/quarantine/2026-08-13/invoice.docx"

LogType 206 — Blocked file deleted

No destination fields. Outcome sentence: The blocked file was deleted.

<110>1 2026-08-13T12:15:53.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta PostAction="Blocked file remediation" fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="1" LogType="206" UserName="system">] "Blocked file remediation" applied to file (fileName: "invoice.docx"; ...) from storage (name: "Finance-SMB"; ...) by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", ...). The blocked file was deleted.

LogType 207 to 215 — Remaining move, copy, delete and keep actions

All share the shape above. The differences are PostAction, LogType, and the outcome sentence.

LogType

Event

PostAction

Outcome sentence

Destination fields

207

Sanitized file moved

Allowed file remediation

The sanitized file was moved to storage ...

yes

208

Allowed file moved

Allowed file remediation

The allowed file was moved to storage ...

yes

209

Blocked file copied

Blocked file remediation

The blocked file was copied to storage ...

yes

210

Sanitized file copied

Allowed file remediation

The sanitized file was copied to storage ...

yes

211

Allowed file copied

Allowed file remediation

The allowed file was copied to storage ...

yes

212

Blocked file kept

Blocked file remediation

The blocked file was kept.

no

213

Allowed file kept

Allowed file remediation

The allowed file was kept.

no

214

Sanitized file kept

Allowed file remediation

The sanitized file was kept on storage ...

yes

215

Allowed file deleted

Allowed file remediation

The allowed file was deleted from storage.

no

221

Sanitized file deleted

Allowed file remediation

The sanitized file was deleted from storage ...

yes

PostAction does not distinguish sanitised from allowed

Sanitised-file remediations report PostAction="Allowed file remediation". Use LogType to identify the specific action, not the PostAction text.

LogType 216 — File versions scanned

PostAction="Scan file versions", no destination fields, no outcome sentence beyond the base text.

<110>1 2026-08-13T12:15:55.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta PostAction="Scan file versions" fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="1" LogType="216" UserName="system">] "Scan file versions" applied to file (fileName: "invoice.docx"; ...) from storage (name: "Finance-SMB"; ...) by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", ...).

LogType 217 to 220 — Discovered file actions

Applied without scanning, by a discovery-only workflow. PostAction="Discovered file remediation".

LogType

Event

Outcome sentence

Destination fields

217

Discovered file deleted

The discovered file was deleted from storage.

no

218

Discovered file moved

The discovered file was moved to storage ...

yes

219

Discovered file copied

The discovered file was copied to storage ...

yes

220

Discovered file kept

The discovered file was kept.

no

<110>1 2026-08-13T12:15:57.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta PostAction="Discovered file remediation" fileName="old-report.xls" filePath="/finance/archive/old-report.xls" fileHash="a87ff679a2f3e71d9181a67b7542122c" fileSize="22100" fileId="0199c0de-7a1e-7000-8000-0000000000af" lastModified="03/02/2024 11:20:00" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="1" LogType="217" UserName="system">] "Discovered file remediation" applied to file (fileName: "old-report.xls"; filePath: "/finance/archive/old-report.xls"; fileHash: "a87ff679a2f3e71d9181a67b7542122c"; fileSize: 22100; fileId: "0199c0de-7a1e-7000-8000-0000000000af"; lastModified: 03/02/2024 11:20:00) from storage (name: "Finance-SMB"; ...) by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", ...). The discovered file was deleted from storage.

Post-action failure

Any post action that fails is emitted at error severity, PRI <107>, with the same LogType and a different message:

<107>1 2026-08-13T12:15:58.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta PostAction="Blocked file remediation" fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="1" LogType="205" UserName="system">] "Blocked file remediation" failed for file (fileName: "invoice.docx"; ...) from storage (name: "Finance-SMB"; ...) by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", ...)

LogType 419 — Empty folders deleted

Folder paths are embedded directly in the message text, not as a field.

<110>1 2026-08-13T12:16:10.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="1" LogType="419" UserName="system">] The following empty folders have been deleted: [/finance/2026/tmp, /finance/2026/old] from storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") by scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process") .

5. Category 2 — Storage units

Category="2".

LogType 300 to 302 — Storage added, updated, removed

LogType

Action

300

added

301

updated

302

removed

Message fields: storageName, storageType, storageId, Action, User.

<110>1 2026-08-13T09:10:22.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" Action="added" User="jdavis" <envelope Category="2" LogType="300" UserName="jdavis">] Storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") was "added" by "jdavis".

Failure variant — error severity, PRI <107>. was becomes could not be:

... Storage (name: "Finance-SMB"; ...) could not be "added" by "jdavis".

LogType 400 — Real-time processing changed

Real-time protection enabled, disabled or reconfigured on a storage.

Enabled, with a backfill start date:

<110>1 2026-08-13T09:12:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="enabled" User="jdavis" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" RealTimeStartDate="2026-08-13T00:00:00.000Z" <envelope Category="2" LogType="400" UserName="jdavis">] Real Time Process was "enabled" by "jdavis" for storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73") discovering files modified since "2026-08-13T00:00:00.000Z"

Disabled — same shape with Action="disabled" and no RealTimeStartDate.

Handling type changed — a different message and a NewHandlingType field:

<110>1 2026-08-13T09:13:30.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta NewHandlingType="EventBased" User="jdavis" storageName="Finance-SMB" storageType="Category: FileShare, Protocol: Smb, Vendor: Generic" storageId="7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73" <envelope Category="2" LogType="400" UserName="jdavis">] Real Time Process handling type was changed to "EventBased" by "jdavis" for storage (name: "Finance-SMB"; "Category: FileShare, Protocol: Smb, Vendor: Generic"; ID: "7f3a9c14-2b8e-4d51-9a06-c1e5b48f2d73")

Failure variant — error severity, PRI <107>, was becomes could not be.


6. Category 3 — Authentication

Category="3".

LogType 600 — Signed in

Message field: User, the account's full name and user name.

<110>1 2026-08-13T12:15:42.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta User="John Davis (jdavis)" <envelope Category="3" LogType="600" UserName="jdavis">] "John Davis (jdavis)" logged in.

Failed sign-ins are not emitted

MDSS 4.5 emits this event only on a successful sign-in. There is no event for a rejected sign-in attempt, so this feed cannot be used for brute-force detection. Where MDSS runs behind SSO, the identity provider's own logs carry authentication failures.

LogType 601 — Signed out

<110>1 2026-08-13T13:02:19.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta User="John Davis (jdavis)" <envelope Category="3" LogType="601" UserName="jdavis">] "John Davis (jdavis)" logged out.

A sign-out that does not complete cleanly is emitted at warning severity, PRI <108>, with the text "John Davis (jdavis)" encountered an issue while logging out.


7. Category 4 — Settings

Category="4". Configuration changes across the product.

LogType 700 to 703 — Scan engine instance changed

Message fields: ScanInstance (the engine URL), Action.

LogType

Action

700

added

701

updated

702

deleted

703

imported

<110>1 2026-08-13T08:40:05.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta ScanInstance="https://core-01:8008" Action="added" <envelope Category="4" LogType="700" UserName="jdavis">] Scan Instance "https://core-01:8008" was "added" by "jdavis".

Failure variant — error severity, PRI <107>, with ResponseMessage:

<107>1 ... [meta Action="add" ScanInstance="https://core-01:8008" ResponseMessage="Connection refused" <envelope Category="4" LogType="700" UserName="jdavis">] Unable to "add" Scan Instance "https://core-01:8008". Response message: "Connection refused".

LogType 750 to 753 — Scan pool changed

Message fields: ScanPool (the pool name), Action. Same actions and failure shape as scan instances.

<110>1 2026-08-13T08:42:11.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta ScanPool="Primary pool" Action="added" <envelope Category="4" LogType="750" UserName="jdavis">] Scan Pool "Primary pool" was "added" by "jdavis".

LogType 800 to 802 — Licence activation

Message fields: Action, User.

LogType

Action

800

online activated

801

offline activated

802

deactivated

<110>1 2026-08-13T08:05:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="online activated " User="jdavis" <envelope Category="4" LogType="800" UserName="jdavis">] License was "online activated " by "jdavis".

Failure variant — error severity, PRI <107>. was becomes failed to be.

LogType 900 — Configuration imported

Message fields: Action, User. The inclusion summary is part of the message text.

<110>1 2026-08-13T08:12:44.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="imported" User="jdavis" <envelope Category="4" LogType="900" UserName="jdavis">] Configuration was "imported" by "jdavis". License was included. SMTP configuration was included. Retention configuration was not included. Notifications configuration was partially included. Users were included

Failure variant — error severity, PRI <107>, with FailureReason:

<107>1 ... [meta Action="imported" User="jdavis" FailureReason="the provided password is incorrect" <envelope Category="4" LogType="900" UserName="jdavis">] Configuration failed to be "imported" by "jdavis" because "the provided password is incorrect".

Other failure reasons: the configuration file could not be upgraded, the configuration file is empty, the license could not be activated, the deserialization of the configuration file has failed, the provided configuration file version is not supported, the configuration file has an invalid structure.

LogType 901 — Configuration exported

Identical shape with Action="exported".

<110>1 2026-08-13T08:14:02.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="exported" User="jdavis" <envelope Category="4" LogType="901" UserName="jdavis">] Configuration was "exported" by "jdavis". License was included. SMTP configuration was included. Retention configuration was included. Notifications configuration was included. Users were not included

LogType 950 — Notification settings changed

Message fields: NotificationType, Action, User.

<110>1 2026-08-13T08:30:10.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta NotificationType="Blocked file notifications" Action="enabled" User="jdavis" <envelope Category="4" LogType="950" UserName="jdavis">] "Blocked file notifications" were "enabled" by "jdavis".

NotificationType is one of: Email notifications for scan reports, Email notifications scan reports recipients, Blocked file notifications, Blocked file notifications recipients, User request notifications, Webhook Scan completed notifications, Webhook Scan completed notifications details, Webhook File scanned notifications details, RabbitMq file scanned notifications details, Email notifications settings, Webhook notifications settings, RabbitMQ notifications settings.

Action is enabled, disabled or updated. Failure variant — error severity, PRI <107>, were becomes could not be.

LogType 950 appears in two categories

With Category="4" it is a settings change, as above. With Category="8" it is a notification delivery result — see section 9. Filter on both fields together.

LogType 975 — SMTP configuration changed

Message fields: Action (enabled, disabled, updated), User.

<110>1 2026-08-13T08:33:20.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="updated" User="jdavis" <envelope Category="4" LogType="975" UserName="jdavis">] SMTP configuration was "updated" by "jdavis".

Failure variant — error severity, PRI <107>, was becomes could not be.

LogType 1000 — External logger added

The server details are embedded in the message text. Message fields: Action, User.

<110>1 2026-08-13T10:01:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="added" User="jdavis" <envelope Category="4" LogType="1000" UserName="jdavis">] External logger (serverAddress: siem.example.com; port: 6514) was "added" by "jdavis".

LogType 1001 — External logger updated

Also used when a destination is enabled or disabled, with Action="enabled" or Action="disabled".

<110>1 2026-08-13T10:03:15.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="disabled" User="jdavis" <envelope Category="4" LogType="1001" UserName="jdavis">] External logger (serverAddress: siem.example.com; port: 6514) was "disabled" by "jdavis".

LogType 1002 — External logger deleted

Action="removed".

<110>1 2026-08-13T10:05:40.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="removed" User="jdavis" <envelope Category="4" LogType="1002" UserName="jdavis">] External logger (serverAddress: siem.example.com; port: 6514) was "removed" by "jdavis".

Failure variants — error severity, PRI <107>. Six distinct messages, all with fields User and Action in present tense (adding, updating, removing, enabling, disabling):

Cause

Message

Duplicate

"jdavis" "adding" external logger failed because one with the same configuration already exists.

Connection test failed

"jdavis" "adding" external logger failed because the configuration is not valid.

Not found

"jdavis" "removing" external logger failed because the configuration does not exist.

Already in that state

"jdavis" "enabling" external logger failed because it was already "enabled".

Limit reached

"jdavis" "adding" external logger failed because because the maximum number of the same integration type was exceeded.

Unexpected error

"jdavis" "adding" external logger failed because an unexpected error occurred.

LogType 1100 — Data retention changed

Message field: User. The detail sentence is part of the message text.

<110>1 2026-08-13T08:50:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta User="John Davis (jdavis)" <envelope Category="4" LogType="1100" UserName="jdavis">] Data retention configuration was successfully updated by "John Davis (jdavis)". Audit logs older than 90 days will be deleted.

Detail sentences, by action:

Action

Success sentence

Failure sentence

Enable report retention

Reports retention is enabled.

Reports retention could not be enabled.

Disable report retention

Reports retention is disabled.

Reports retention could not be disabled.

Change report retention days

Reports older than 90 days will be deleted.

Retention days could not be updated for reports.

Change audit retention days

Audit logs older than 90 days will be deleted.

Retention days could not be updated for audit logs.

Change RTP history retention days

Files processed during Real-Time Processing older than 30 days will be deleted.

Retention days could not be updated for Real-Time Processing history.

On failure, severity is error, PRI <107>, and was successfully becomes could not be.

LogType 1200 to 1202 — API key changed

The key value is truncated to its first six characters. Message fields: TruncatedAPIKey, Action, User.

LogType

Action

1200

added

1201

updated

1202

deleted

<110>1 2026-08-13T09:00:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta TruncatedAPIKey="a3f9c1" Action="added" User="John Davis (jdavis)" <envelope Category="4" LogType="1200" UserName="jdavis">] API Key "a3f9c1..." was "added" by "John Davis (jdavis)".

Failure variant — error severity, PRI <107>, with FailureReason:

<107>1 ... [meta User="John Davis (jdavis)" Action="add" TruncatedAPIKey="a3f9c1" FailureReason="an API Key with the same value already exists" <envelope Category="4" LogType="1200" UserName="jdavis">] User "John Davis (jdavis)" was unable to "add" API Key "a3f9c1" because "an API Key with the same value already exists".

Other failure reasons: an unexpected error occurred, the requested user was not found, the requested API Key was not found, a key rotation is currently in progress.

API key usage is not audited

These events cover the key's lifecycle only. Requests authenticated with an API key do not produce audit events.

LogType 1300 — SSO configuration changed

Enabled or reconfigured — fields User, SsoType, SsoProvider, Authority:

<110>1 2026-08-13T09:05:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta User="John Davis (jdavis)" SsoType="Oidc" SsoProvider="AzureAd" Authority="https://login.microsoftonline.com/contoso" <envelope Category="4" LogType="1300" UserName="jdavis">] "John Davis (jdavis)" changed Single Sign-On configuration to type "Oidc", provider "AzureAd", authority "https://login.microsoftonline.com/contoso".

Disabled — field User only:

<110>1 ... [meta User="John Davis (jdavis)" <envelope Category="4" LogType="1300" UserName="jdavis">] "John Davis (jdavis)" disabled Single Sign-On configuration.

Failure variant — error severity, PRI <107>:

<107>1 ... [meta User="John Davis (jdavis)" <envelope Category="4" LogType="1300" UserName="jdavis">] "John Davis (jdavis)" tried to change the Single Sign-On configuration, but failed.

LogType 1410 — Workflow scanning modules changed

Message fields: WorkflowId, Technologies.

<110>1 2026-08-13T09:30:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta WorkflowId="9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" Technologies="Antimalware, DeepCdr, VulnerabilityAssessment" <envelope Category="4" LogType="1410" UserName="jdavis">] Scanning modules for Workflow "9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" have been updated. New values: "Antimalware, DeepCdr, VulnerabilityAssessment".

LogType 1600 — On-demand scan requested

Single file — file identity fields plus UserName:

<110>1 2026-08-13T11:20:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta fileName="invoice.docx" filePath="/finance/2026/invoice.docx" fileHash="5d41402abc4b2a76b9719d911017c592" fileSize="48213" fileId="0199c0de-7a1e-7000-8000-0000000000ab" lastModified="08/12/2026 16:40:11" UserName="jdavis" <envelope Category="4" LogType="1600" UserName="jdavis">] Successfully sent request to scan file on demand (fileName: "invoice.docx"; filePath: "/finance/2026/invoice.docx"; fileHash: "5d41402abc4b2a76b9719d911017c592"; fileSize: 48213; fileId: "0199c0de-7a1e-7000-8000-0000000000ab"; lastModified: 08/12/2026 16:40:11) . Action performed by "jdavis"

Filtered rescan of many files — scan fields instead of file fields:

<110>1 2026-08-13T11:22:30.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" UserName="jdavis" <envelope Category="4" LogType="1600" UserName="jdavis">] Successfully sent request to rescan multiple files on demand for (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process") . Action performed by "jdavis"

LogType 2000 — Encryption key event

Key generation — fields Action and ActionAndUser:

<110>1 2026-08-13T02:00:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Action="Started" ActionAndUser="was started by John Davis (jdavis)" <envelope Category="4" LogType="2000" UserName="jdavis">] Key generation "was started by John Davis (jdavis)".

Completion reads Key generation "was completed". Failure reads Key generation "failed". at error severity, PRI <107>.

Request cancelled during key rotation — field Request:

<108>1 2026-08-13T02:00:30.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Request=" POST /api/storage" <envelope Category="4" LogType="2000" UserName="jdavis">] Request " POST /api/storage" was cancelled because a key rotation is currently in progress.

LogType 2200 — HTTPS certificate changed

Message fields: ActionMessage, User.

<110>1 2026-08-13T07:45:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta ActionMessage="enabled, and certificate was updated" User="John Davis (jdavis)" <envelope Category="4" LogType="2200" UserName="jdavis">] HTTPS was "enabled, and certificate was updated" by "John Davis (jdavis)".

Disabling reads HTTPS was "disabled" by "John Davis (jdavis)".

LogType 2300 — Telemetry configuration changed

Message field: Status. Emitted by the system on startup reconciliation, or by an administrator.

<110>1 2026-08-13T07:30:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Status="enabled" <envelope Category="4" LogType="2300" UserName="jdavis">] Telemetry configuration was updated. Status: "enabled"

8. Category 6 — Users

Category="6".

LogType 602 to 606 — User account changed

Message fields: Username (the account acted on), Action.

LogType

Event

Action

Message

602

User created

created

User "mrossi" was "created".

603

User registered

registered

User "mrossi" was "registered".

604

User role updated

updated

User "mrossi"'s role was "updated".

605

User updated

updated

User "mrossi" was "updated".

605

Password reset

reset

User "mrossi"'s password was "reset".

<110>1 2026-08-13T09:40:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Username="mrossi" Action="created" <envelope Category="6" LogType="602" UserName="mrossi">] User "mrossi" was "created".

Role update:

<110>1 2026-08-13T09:41:15.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Username="mrossi" Action="updated" <envelope Category="6" LogType="604" UserName="mrossi">] User "mrossi"'s role was "updated".

Removal uses LogType="606" with Action="removed".

Password reset shares LogType 605 with user update

Both are LogType="605". Distinguish them by the message text or the Action field — reset versus updated.

Failure variant — error severity, PRI <107>:

<107>1 ... [meta Username="mrossi" Action="created" <envelope Category="6" LogType="602" UserName="mrossi">] User "mrossi" could not be "created".

The actor is the account acted on, not the administrator

On these events UserName and UserId identify the user being created, updated or removed. The administrator who performed the action appears in the message text only when MDSS has it, so do not rely on the envelope to identify the operator here.

LogType 1800 — Product tour finalised

Message fields: UserName, TourType.

<110>1 2026-08-13T09:50:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta UserName="jdavis" TourType="Onboarding" <envelope Category="6" LogType="1800" UserName="jdavis">] User "jdavis" finalized user tour "Onboarding".

9. Category 8 — Notifications

Category="8". Delivery results for outbound notifications. All emitted by the system, so UserName="system".

LogType 950 — Email notification sent

Recipients and the notification description are embedded in the message text; there are no message fields.

<110>1 2026-08-13T12:16:20.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta <envelope Category="8" LogType="950" UserName="system">] Email notification for blocked file invoice.docx was sent to: soc@example.com, ciso@example.com

Notification descriptions, by type:

Type

Description text

Report generated

Email notification that contains the scan Nightly Finance report

New user registered

Email notification for the new registered user

User request processed

Email notification after user request was processed

Password reset

Email notification that contains the password reset details

Password reset completed

Email confirmation after password reset

Blocked file

Email notification for blocked file invoice.docx

User updated

Email confirmation after user update

Generic

Email notification

Partial delivery failure — the message names both sets of recipients:

<110>1 ... [meta <envelope Category="8" LogType="950" UserName="system">] Email notification for blocked file invoice.docx was sent to: soc@example.com Email could not be sent to: ciso@example.com

Total delivery failure — error severity, PRI <107>:

<107>1 ... [meta <envelope Category="8" LogType="950" UserName="system">] Email notification for blocked file invoice.docx could not be sent to: soc@example.com, ciso@example.com

No recipient configured — error severity, PRI <107>:

<107>1 ... [meta <envelope Category="8" LogType="950" UserName="system">] Email notification for blocked file invoice.docx could not be sent. The recipient could not be found.

LogType 950 — Webhook notification sent

Message field: ScanName or FileName.

<110>1 2026-08-13T12:16:25.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta ScanName="Nightly Finance" <envelope Category="8" LogType="950" UserName="system">] Webhook notification for completion of scan "Nightly Finance" was successfully sent
<110>1 2026-08-13T12:16:26.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta FileName="invoice.docx" <envelope Category="8" LogType="950" UserName="system">] Webhook notification for scanned file "invoice.docx" was successfully sent

Failure variants — error severity, PRI <107>: Failed to send webhook notification for scan "Nightly Finance" and Failed to send webhook notification for scanned file "invoice.docx".

LogType 950 — Message-queue notification sent

Message field: FileName.

<110>1 2026-08-13T12:16:27.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta FileName="invoice.docx" <envelope Category="8" LogType="950" UserName="system">] RabbitMQ notification for scanned file "invoice.docx" was successfully sent

Failure variant — error severity, PRI <107>: Failed to send RabbitMQ notification for scanned file "invoice.docx".

LogType 1700 — Report generated

Message fields: scan fields.

<110>1 2026-08-13T12:20:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta scanId="e1b6d842-0f37-4c9b-8a15-63d0947fe2ba" scanName="Nightly Finance" scanType="Scheduled Process" <envelope Category="8" LogType="1700" UserName="system">] PDF Report of scan (ID: "e1b6d842-0f37-4c9b-8a15-63d0947fe2ba", name: "Nightly Finance", type: "Scheduled Process") has been created

10. Category 9 — Group units

Category="9".

LogType 320 to 322 — Group added, updated, removed

Message fields: groupName, groupId, Action, User.

LogType

Action

320

added

321

updated

322

removed

<110>1 2026-08-13T09:15:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta groupName="Finance shares" groupId="4e7c9105-8d26-4a3f-b012-75ea3c6f81db" Action="added" User="jdavis" <envelope Category="9" LogType="320" UserName="jdavis">] Group (name: "Finance shares"; ID: "4e7c9105-8d26-4a3f-b012-75ea3c6f81db") was "added" by "jdavis".

Failure variant — error severity, PRI <107>, was becomes could not be.


11. Category 10 — Account units

Category="10".

LogType 330 to 332 — Account added, updated, removed

Message fields: accountName, accountId, Action, User.

LogType

Action

330

added

331

updated

332

removed

<110>1 2026-08-13T09:17:30.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta accountName="contoso-svc" accountId="6f18b3d4-9e07-42ca-8b53-1d904af7e26c" Action="added" User="jdavis" <envelope Category="10" LogType="330" UserName="jdavis">] Account (name: "contoso-svc"; ID: "6f18b3d4-9e07-42ca-8b53-1d904af7e26c") was "added" by "jdavis".

Failure variant — error severity, PRI <107>, was becomes could not be.


12. Category 11 — Remediations

Category="11". Changes to remediation rules. Rule execution appears in category 1.

LogType 2101 to 2103 — Remediation rule added, updated, deleted

Message fields: Type, HandlingType, WorkflowId, WorkflowName, Action, UserName.

LogType

Action

2101

added

2102

updated

2103

deleted

<110>1 2026-08-13T09:35:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta Type="BlockedFileRemediation" HandlingType="Move" WorkflowId="9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" WorkflowName="Default workflow" Action="added" UserName="jdavis" <envelope Category="11" LogType="2101" UserName="jdavis">] Remediation of type "BlockedFileRemediation" with "Move" action for Workflow (Id: "9d4e1f60-3a72-4b85-8c19-f2073be5a1c8"; Name: "Default workflow") was "added" by "jdavis".

Type is one of FileTagging, BlockedFileRemediation, AllowedFileRemediation, AllowedSanitizedFileRemediation, BlockedSanitizedFileRemediation, DiscoveredFileRemediation, DeepCdr, DeleteEmptyFoldersRemediation, ScanFileVersions. HandlingType is Move, Copy, Delete, Keep or NotApplicable.

Rule disabled — no HandlingType:

<110>1 ... [meta Type="BlockedFileRemediation" WorkflowId="9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" WorkflowName="Default workflow" UserName="jdavis" <envelope Category="11" LogType="2102" UserName="jdavis">] Remediation of type "BlockedFileRemediation" was disabled for Workflow (Id: "9d4e1f60-3a72-4b85-8c19-f2073be5a1c8"; Name: "Default workflow") by "jdavis".

Empty-folder remediation — adds a Depth field:

<110>1 ... [meta Type="DeleteEmptyFoldersRemediation" WorkflowId="9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" WorkflowName="Default workflow" Depth="3" Action="added" UserName="jdavis" <envelope Category="11" LogType="2101" UserName="jdavis">] Remediation of type "DeleteEmptyFoldersRemediation" for Workflow (Id: "9d4e1f60-3a72-4b85-8c19-f2073be5a1c8"; Name: "Default workflow") with folder depth: 3 was "added" by "jdavis".

Failure variant — error severity, PRI <107>:

<107>1 ... [meta Type="BlockedFileRemediation" WorkflowId="9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" WorkflowName="Default workflow" <envelope Category="11" LogType="2101" UserName="jdavis">] Unable to use remediation of "BlockedFileRemediation" for Workflow (Id: "9d4e1f60-3a72-4b85-8c19-f2073be5a1c8"; Name: "Default workflow")

13. Category 12 — Workflows

Category="12".

LogType 1400 to 1404 — Workflow changed

Message fields: WorkflowId, WorkflowName, Action, UserName, and — except on delete — FileDefinitionMode.

LogType

Action

1400

added

1401

updated

1402

deleted

1403

set as default

1404

imported

<110>1 2026-08-13T09:32:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta WorkflowId="9d4e1f60-3a72-4b85-8c19-f2073be5a1c8" WorkflowName="Default workflow" Action="added" UserName="jdavis" FileDefinitionMode="Strict" <envelope Category="12" LogType="1400" UserName="jdavis">] Workflow (Id: "9d4e1f60-3a72-4b85-8c19-f2073be5a1c8"; Name: "Default workflow") was "added" by "jdavis". File Definition: mode - "Strict"

With the configurable blocking strategy, FileDefinitionMode="Configurable" and the message lists the individual blocking options.

Failure variant — error severity, PRI <107>, with ErrorMessage:

<107>1 ... [meta Action="add" Workflow="Default workflow" ErrorMessage="A workflow with this name already exists" UserName="jdavis" FileDefinitionMode="Strict" <envelope Category="12" LogType="1400" UserName="jdavis">] Unable to "add" Workflow "Default workflow". Response message: "A workflow with this name already exists". Action performed by "jdavis". File Definition: mode - "Strict"

14. Category 13 — Access control

Category="13". Role and permission assignment. Message field: User. The description is part of the message text.

LogType 2400 to 2412

LogType

Event

Success message

Failure message

2400

Role assigned

Role was assigned to a user by "John Davis (jdavis)".

Role could not be assigned to a user by "John Davis (jdavis)".

2401

Role removed

Role was removed from a user by "John Davis (jdavis)".

Role could not be removed from a user by "John Davis (jdavis)".

2402

Custom role created

Custom role was created by "John Davis (jdavis)".

Custom role could not be created by "John Davis (jdavis)".

2403

Custom role deleted

Custom role was deleted by "John Davis (jdavis)".

Custom role could not be deleted by "John Davis (jdavis)".

2410

Permission assigned

Permission was assigned to a user by "John Davis (jdavis)".

Permission could not be assigned to a user by "John Davis (jdavis)".

2411

Permission removed

Permission was removed from a user by "John Davis (jdavis)".

Permission could not be removed from a user by "John Davis (jdavis)".

2412

Roles replaced

Roles were replaced for a user by "John Davis (jdavis)".

Roles could not be replaced for a user by "John Davis (jdavis)".

<110>1 2026-08-13T09:45:00.000000+02:00 mdss-prod-01 MetaDefenderStorageSecurity 27725 - [meta User="John Davis (jdavis)" <envelope Category="13" LogType="2400" UserName="jdavis">] Role was assigned to a user by "John Davis (jdavis)".

Failure variants are emitted at error severity, PRI <107>.

The affected user is not a field

These events name the administrator who made the change, not the user whose access changed. The target user is not carried on the event.


15. Reserved event types

The schema defines 112 event types. The 14 below are reserved and are not emitted by MDSS 4.5. Do not build rules that depend on them.

LogType

Reserved name

201

File sanitized, original kept

203

File sanitized, original deleted

204

File decryption

350

Security checklist item

351

Security checklist verified

410

File tagging

411

Deep CDR remediation

412

Sanitized files remediation

413

Blocked files remediation

414

Treat files with sensitive data as blocked

415

Treat files with vulnerabilities as blocked

416

Allowed files remediation

417

Strict block files strategy

418

Configurable block files strategy

Category 7 (security checklist) is reserved for the same reason, and category 5 is not defined.

Parsers should handle unrecognised LogType and Category values without failing — new values may be added in later releases.


16. Quick index

LogType

Event

Category

0

File discovered

0

1

File scanned

0

2

File discovery failed or skipped

0

3

File cancelled

0

100

Scan process started

0

101

Scan process completed

0

102

Scan process cancelled

0

103

Scan process failed

0

200

File tagged

1

205

Blocked file moved

1

206

Blocked file deleted

1

207

Sanitized file moved

1

208

Allowed file moved

1

209

Blocked file copied

1

210

Sanitized file copied

1

211

Allowed file copied

1

212

Blocked file kept

1

213

Allowed file kept

1

214

Sanitized file kept

1

215

Allowed file deleted

1

216

File versions scanned

1

217

Discovered file deleted

1

218

Discovered file moved

1

219

Discovered file copied

1

220

Discovered file kept

1

221

Sanitized file deleted

1

300

Storage added

2

301

Storage updated

2

302

Storage removed

2

320

Group added

9

321

Group updated

9

322

Group removed

9

330

Account added

10

331

Account updated

10

332

Account removed

10

400

Real-time processing changed

2

419

Empty folders deleted

1

600

Signed in

3

601

Signed out

3

602

User created

6

603

User registered

6

604

User role updated

6

605

User updated or password reset

6

606

User removed

6

700

Scan instance added

4

701

Scan instance updated

4

702

Scan instance deleted

4

703

Scan instance imported

4

750

Scan pool added

4

751

Scan pool updated

4

752

Scan pool deleted

4

753

Scan pool imported

4

800

Licence activated online

4

801

Licence activated offline

4

802

Licence deactivated

4

900

Configuration imported

4

901

Configuration exported

4

950

Notification settings changed

4

950

Notification delivery result

8

975

SMTP configuration changed

4

1000

External logger added

4

1001

External logger updated, enabled or disabled

4

1002

External logger deleted

4

1100

Data retention changed

4

1200

API key added

4

1201

API key updated

4

1202

API key deleted

4

1300

SSO configuration changed

4

1400

Workflow added

12

1401

Workflow updated

12

1402

Workflow deleted

12

1403

Workflow set as default

12

1404

Workflow imported

12

1410

Workflow scanning modules changed

4

1500

Scan added

0

1501

Scan updated

0

1502

Scan deleted

0

1503

Scan imported

0

1600

On-demand scan requested

4

1700

Report generated

8

1800

Product tour finalised

6

1900

Scan schedule added

0

1901

Scan schedule updated

0

1902

Scan schedule deleted

0

1903

Scan schedule imported

0

1904

Scan schedule skipped

0

2000

Encryption key event

4

2101

Remediation rule added

11

2102

Remediation rule updated

11

2103

Remediation rule deleted

11

2200

HTTPS certificate changed

4

2300

Telemetry configuration changed

4

2400

Role assigned

13

2401

Role removed

13

2402

Custom role created

13

2403

Custom role deleted

13

2410

Permission assigned

13

2411

Permission removed

13

2412

Roles replaced

13


On This Page
Syslog Message Reference — One Sample per Event Type1. Message anatomy2. Reading the actor fields3. Category 0 — Scan activities4. Category 1 — Post actions5. Category 2 — Storage units6. Category 3 — Authentication7. Category 4 — Settings8. Category 6 — Users9. Category 8 — Notifications10. Category 9 — Group units11. Category 10 — Account units12. Category 11 — Remediations13. Category 12 — Workflows14. Category 13 — Access control15. Reserved event types16. Quick indexWhat is inside [meta ...]Two conventions to noteA complete exampleSample environmentLogType 0 — File discoveredLogType 1 — File scannedLogType 2 — File discovery failedLogType 3 — File cancelledLogType 100 to 103 — Scan process lifecycleLogType 1500 to 1503 — Scan configuration changedLogType 1900 to 1904 — Scan schedule changedLogType 200 — File taggedLogType 205 — Blocked file movedLogType 206 — Blocked file deletedLogType 207 to 215 — Remaining move, copy, delete and keep actionsLogType 216 — File versions scannedLogType 217 to 220 — Discovered file actionsPost-action failureLogType 419 — Empty folders deletedLogType 300 to 302 — Storage added, updated, removedLogType 400 — Real-time processing changedLogType 600 — Signed inLogType 601 — Signed outLogType 700 to 703 — Scan engine instance changedLogType 750 to 753 — Scan pool changedLogType 800 to 802 — Licence activationLogType 900 — Configuration importedLogType 901 — Configuration exportedLogType 950 — Notification settings changedLogType 975 — SMTP configuration changedLogType 1000 — External logger addedLogType 1001 — External logger updatedLogType 1002 — External logger deletedLogType 1100 — Data retention changedLogType 1200 to 1202 — API key changedLogType 1300 — SSO configuration changedLogType 1410 — Workflow scanning modules changedLogType 1600 — On-demand scan requestedLogType 2000 — Encryption key eventLogType 2200 — HTTPS certificate changedLogType 2300 — Telemetry configuration changedLogType 602 to 606 — User account changedLogType 1800 — Product tour finalisedLogType 950 — Email notification sentLogType 950 — Webhook notification sentLogType 950 — Message-queue notification sentLogType 1700 — Report generatedLogType 320 to 322 — Group added, updated, removedLogType 330 to 332 — Account added, updated, removedLogType 2101 to 2103 — Remediation rule added, updated, deletedLogType 1400 to 1404 — Workflow changedLogType 2400 to 2412