Votiro - File Blocked in Email

Severity: low
Time window: 10m
Group by: FileWithEmailDetails, LogSeverity, SrcFileSHA256, fileName, policyName, sanitizationResult
Source: github.com/Azure/Azure-Sentinel

'The analytic rule is designed to identify when an email is blocked by Votiro Sanitization Engine policy. The rule generates an alert when an email is blocked after Sanitization process which is not password protected and has a from field meaning its a valid email. More information in terms of details about the blocked attachment, such as the file name and hash, and information about the email, such as the sender and recipient(s). The alert also includes information about the Votiro policy that blocked the attachment and provides a link to additional details about the incident.'

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1566` Phishing
Stealth	`T1027` Obfuscated Files or Information, `T1036` Masquerading
Impact	`T1486` Data Encrypted for Impact
Command and Control	`T0885` Commonly Used Port

Rule body kusto

id: 0b8b91de-c63e-4bc2-b5f4-b15d3b379ec9
name: Votiro - File Blocked in Email
description: |
 'The analytic rule is designed to identify when an email is blocked by Votiro Sanitization Engine policy. The rule generates an alert when an email is blocked after Sanitization process which is not password protected and has a from field meaning its a valid email. More information in terms of details about the blocked attachment, such as the file name and hash, and information about the email, such as the sender and recipient(s). The alert also includes information about the Votiro policy that blocked the attachment and provides a link to additional details about the incident.'
severity: Low
requiredDataConnectors:
  - connectorId: Votiro
    dataTypes:
      - CommonSecurityLog 
  - connectorId: CefAma
    dataTypes:
      - CommonSecurityLog
queryFrequency: 10m
queryPeriod: 10m
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CommandAndControl
  - DefenseEvasion
  - Impact
  - InitialAccess
relevantTechniques:
  - T0885
  - T1036
  - T1027
  - T1486
  - T1566
query: let Votiro_view  = view () {
  VotiroEvents
   | where sanitizationResult has "Blocked" and passwordProtected == "false" and from =~ "null"
   | extend FileWithEmailDetails = strcat_delim(' ', fileName, 'with the hash', SrcFileSHA256, 'was blocked in an email that was sent from user', from, 'to the following recipients', recipients)
   | summarize count() by fileName, SrcFileSHA256, FileWithEmailDetails, policyName, tostring(incidentURL), sanitizationResult, LogSeverity
   | extend FileHashAlgo = "SHA256", FileHashValue = SrcFileSHA256};Votiro_view
entityMappings:
- entityType: FileHash
  fieldMappings:
    - identifier: Algorithm
      columnName: FileHashAlgo
    - identifier: Value
      columnName: FileHashValue
incidentConfiguration:
  createIncident: true
eventGroupingSettings:
  aggregationKind: AlertPerResult
alertDetailsOverride: 
   alertDisplayNameFormat: File with hash {{SrcFileSHA256}} was blocked
   alertDescriptionFormat: Attachment {{FileWithEmailDetails}} by Votiro due to Policy rules, see more detail in the following link {{incidentURL}}
   alertTacticsColumnName: sanitizationResult
   alertSeverityColumnName: LogSeverity
version: 1.0.1
kind: Scheduled

Stages and Predicates

Let binding: `Votiro_view`

let Votiro_view = view () { VotiroEvents | where sanitizationResult has "Blocked" and passwordProtected == "false" and from =~ "null" | extend FileWithEmailDetails = strcat_delim(' ', fileName, 'with the hash', SrcFileSHA256, 'was blocked in an email that was sent from user', from, 'to the following recipients', recipients) | summarize count() by fileName, SrcFileSHA256, FileWithEmailDetails, policyName, tostring(incidentURL), sanitizationResult, LogSeverity | extend FileHashAlgo = "SHA256", FileHashValue = SrcFileSHA256};

Stage 1: `source`

VotiroEvents

Stage 2: `where`

where from =~ "null" and passwordProtected =~ false and sanitizationResult contains "Blocked"

Stage 3: `extend`

extend FileWithEmailDetails

Stage 4: `summarize`

summarize by fileName, SrcFileSHA256, FileWithEmailDetails, policyName, sanitizationResult, LogSeverity

Stage 5: `extend`

extend FileHashAlgo, FileHashValue

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`from`	eq	`null`
`passwordProtected`	eq	`false` transforms: `cased`
`sanitizationResult`	match	`Blocked` transforms: `term`

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

Field	Source
`FileWithEmailDetails`	`summarize`
`LogSeverity`	`summarize`
`SrcFileSHA256`	`summarize`
`fileName`	`summarize`
`policyName`	`summarize`
`sanitizationResult`	`summarize`
`FileHashAlgo`	`extend`
`FileHashValue`	`extend`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)

Votiro - File Blocked in Email

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Let binding: `Votiro_view`

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `summarize`

Stage 5: `extend`

Indicators

Output fields

Keyboard shortcuts

Search operators

Votiro - File Blocked in Email

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Let binding: Votiro_view

Stage 1: source

Stage 2: where

Stage 3: extend

Stage 4: summarize

Stage 5: extend

Indicators

Output fields

Let binding: `Votiro_view`

Stage 1: `source`

Stage 2: `where`

Stage 3: `extend`

Stage 4: `summarize`

Stage 5: `extend`