Detection rules › Kusto
Antivirus Detected an Infected File
Monitors CTERA platform to detect files infected with viruses identified by the antivirus engine on Edge Filers.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | T1203 Exploitation for Client Execution |
Rule body kusto
id: 4f767afa-d666-4ed4-b453-a4f5ad35181b
name: Antivirus Detected an Infected File
description: 'Monitors CTERA platform to detect files infected with viruses identified by the antivirus engine on Edge Filers.'
severity: High
status: Available
kind: NRT
requiredDataConnectors:
- connectorId: CTERA
dataTypes:
- Syslog
tactics:
- Impact
relevantTechniques:
- T1203
query: |
Syslog
| where SyslogMessage contains "found an infected file"
| extend
EdgeFiler = extract("Edge filer (\\w+)", 1, SyslogMessage),
DetectionTime = extract("found an infected file at ([^ ]+)", 1, SyslogMessage),
Portal = extract("from portal: (\\w+)", 1, SyslogMessage),
FilePath = extract("The file path is: ([^\\.]+)", 1, SyslogMessage),
Virus = extract("The virus is: ([^\\.]+)", 1, SyslogMessage)
| project TimeGenerated, EdgeFiler, DetectionTime, Portal, FilePath, Virus
suppressionDuration: PT5H
suppressionEnabled: false
incidentConfiguration:
createIncident: true
groupingConfiguration:
enabled: false
reopenClosedIncident: false
lookbackDuration: PT5H
matchingMethod: AllEntities
eventGroupingSettings:
aggregationKind: SingleAlert
alertDetailsOverride:
alertnameFormat: 'Antivirus Detected an Infected File'
alertDescriptionFormat: Antivirus detected an infected file on {{EdgeFiler}} at {{DetectionTime}}.
customDetails:
EdgeFiler: EdgeFiler
Portal: Portal
FilePath: FilePath
Virus: Virus
entityMappings:
- entityType: Host
fieldMappings:
- identifier: HostName
columnName: EdgeFiler
version: 1.0.0
Stages and Predicates
Stage 1: source
Syslog
Stage 2: where
| where SyslogMessage contains "found an infected file"
Stage 3: extend
| extend
EdgeFiler = extract("Edge filer (\\w+)", 1, SyslogMessage),
DetectionTime = extract("found an infected file at ([^ ]+)", 1, SyslogMessage),
Portal = extract("from portal: (\\w+)", 1, SyslogMessage),
FilePath = extract("The file path is: ([^\\.]+)", 1, SyslogMessage),
Virus = extract("The virus is: ([^\\.]+)", 1, SyslogMessage)
Stage 4: project
| project TimeGenerated, EdgeFiler, DetectionTime, Portal, FilePath, Virus
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 |
|---|---|---|
SyslogMessage | contains |
|
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 |
|---|---|
DetectionTime | project |
EdgeFiler | project |
FilePath | project |
Portal | project |
TimeGenerated | project |
Virus | project |