Detection rules › Kusto

Vaikora - Anomaly detection

This is a third-party alert feed, not a detection over modeled telemetry. The vendor product raised the finding; this rule forwards it into the SIEM. It is searchable for reference but is excluded from the detection-rule browse and the ATT&CK coverage matrix.

Status: available
Severity: medium
Time window: 6h
Source: github.com/Azure/Azure-Sentinel

Identifies actions flagged as anomalies or confirmed threats by Vaikora. Catches behavioral anomalies that fall below high/critical severity but still represent statistically unusual activity worth investigating.

MITRE ATT&CK coverage

Tactic	Techniques
Discovery	No specific technique
Lateral Movement	No specific technique
Collection	No specific technique
Exfiltration	No specific technique

Rule body kusto

id: c0984707-0855-430e-9c36-5e2d0d0ce56f
name: Vaikora - Anomaly detection
description: |
  Identifies actions flagged as anomalies or confirmed threats by Vaikora. Catches behavioral anomalies that fall below high/critical severity but still represent statistically unusual activity worth investigating.
severity: Medium
requiredDataConnectors:
  - connectorId: VaikoraSecurityCenter
    dataTypes:
      - Vaikora_SecurityAlerts_CL
queryFrequency: 6h
queryPeriod: 6h
triggerOperator: gt
triggerThreshold: 0
status: Available
tactics:
  - Discovery
  - LateralMovement
  - Collection
  - Exfiltration
relevantTechniques: []
query: |
  Vaikora_SecurityAlerts_CL
  | where TimeGenerated >= ago(6h)
  | where IsAnomaly_b == true or ThreatDetected_b == true
  | where Severity_s !in ("high", "critical")
  | extend
      AlertId       = AlertId_s,
      AgentId       = AgentId_s,
      ActionType    = ActionType_s,
      Severity      = Severity_s,
      Title         = Title_s,
      Description   = Description_s,
      SourceIP      = SourceIP,
      DestinationIP = DestinationIP_s,
      SourceHost    = SourceHost_s,
      DestHost      = DestinationHost_s,
      ProcessName   = ProcessName_s,
      UserName      = UserName_s,
      FilePath      = FilePath_s,
      Confidence    = ConfidenceScore_d,
      ThreatFlag    = ThreatDetected_b,
      AnomalyFlag   = IsAnomaly_b
  | project
      TimeGenerated, AlertId, AgentId, ActionType, Severity, Title, Description,
      SourceIP, DestinationIP, SourceHost, DestHost, ProcessName, UserName, FilePath,
      Confidence, ThreatFlag, AnomalyFlag
  | order by Confidence desc, TimeGenerated desc
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: SourceIP
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: SourceHost
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: UserName
alertDetailsOverride:
  alertDisplayNameFormat: "Vaikora Anomaly: {{Title_s}} (confidence: {{ConfidenceScore_d}})"
  alertDescriptionFormat: "Vaikora AI detected a threat on agent {{AgentId_s}} (ThreatDetected={{ThreatDetected_b}}). {{Description_s}}"
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: `source`

Vaikora_SecurityAlerts_CL

Stage 2: `where`

| where TimeGenerated >= ago(6h)

Stage 3: `where`

| where IsAnomaly_b == true or ThreatDetected_b == true

Stage 4: `where`

| where Severity_s !in ("high", "critical")

Stage 5: `extend`

| extend
    AlertId       = AlertId_s,
    AgentId       = AgentId_s,
    ActionType    = ActionType_s,
    Severity      = Severity_s,
    Title         = Title_s,
    Description   = Description_s,
    SourceIP      = SourceIP,
    DestinationIP = DestinationIP_s,
    SourceHost    = SourceHost_s,
    DestHost      = DestinationHost_s,
    ProcessName   = ProcessName_s,
    UserName      = UserName_s,
    FilePath      = FilePath_s,
    Confidence    = ConfidenceScore_d,
    ThreatFlag    = ThreatDetected_b,
    AnomalyFlag   = IsAnomaly_b

Stage 6: `project`

| project
    TimeGenerated, AlertId, AgentId, ActionType, Severity, Title, Description,
    SourceIP, DestinationIP, SourceHost, DestHost, ProcessName, UserName, FilePath,
    Confidence, ThreatFlag, AnomalyFlag

Stage 7: `sort`

| order by Confidence desc, TimeGenerated desc

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

Field	Kind	Excluded values
`Severity_s`	in	`critical`, `high`

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
`IsAnomaly_b`	eq	`true` transforms: `cased`
`ThreatDetected_b`	eq	`true` transforms: `cased`

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
`ActionType`	`project`
`AgentId`	`project`
`AlertId`	`project`
`AnomalyFlag`	`project`
`Confidence`	`project`
`Description`	`project`
`DestHost`	`project`
`DestinationIP`	`project`
`FilePath`	`project`
`ProcessName`	`project`
`Severity`	`project`
`SourceHost`	`project`
`SourceIP`	`project`
`ThreatFlag`	`project`
`TimeGenerated`	`project`
`Title`	`project`
`UserName`	`project`

`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)

Vaikora - Anomaly detection

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `where`

Stage 5: `extend`

Stage 6: `project`

Stage 7: `sort`

Exclusions

Indicators

Output fields

Keyboard shortcuts

Search operators

Vaikora - Anomaly detection

MITRE ATT&CK coverage

Rule body kusto

Stages and Predicates

Stage 1: source

Stage 2: where

Stage 3: where

Stage 4: where

Stage 5: extend

Stage 6: project

Stage 7: sort

Exclusions

Indicators

Output fields

Stage 1: `source`

Stage 2: `where`

Stage 3: `where`

Stage 4: `where`

Stage 5: `extend`

Stage 6: `project`

Stage 7: `sort`