Detection rules › Kusto
Contrast Probes
'Creates Incidents for Probed events sourced from the Contrast Protect agent.'
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access | T1566 Phishing |
Rule body kusto
id: 297596de-d9ae-4fb8-b6ff-00fc01c9462d
name: Contrast Probes
description: |
'Creates Incidents for Probed events sourced from the Contrast Protect agent.'
severity: Informational
requiredDataConnectors:
- connectorId: ContrastProtect
dataTypes:
- CommonSecurityLog
- connectorId: ContrastProtectAma
dataTypes:
- CommonSecurityLog
- connectorId: CefAma
dataTypes:
- CommonSecurityLog
queryFrequency: 5m
queryPeriod: 5m
triggerOperator: gt
triggerThreshold: 10
status: Available
tactics:
- InitialAccess
- Exfiltration
relevantTechniques:
- T1566
query: |
let extract_data=(a:string, k:string) {
parse_urlquery(replace(@';', @'&', a))["Query Parameters"][k]
};
CommonSecurityLog
| where DeviceVendor == "Contrast Security"
| where AdditionalExtensions contains "PROBED" or AdditionalExtensions contains "INEFFECTIVE"
| extend DeviceProduct
| extend SourceIP
| extend DeviceVersion
| extend Activity
| extend ApplicationProtocol
| extend RequestURL
| extend RequestMethod
| extend Rule = extract_data(AdditionalExtensions, 'pri')
customDetails:
Application: ApplicationProtocol
Agent: DeviceProduct
AgentVersion: DeviceVersion
Attack: Activity
Details: AdditionalExtensions
entityMappings:
- entityType: IP
fieldMappings:
- identifier: Address
columnName: SourceIP
- entityType: URL
fieldMappings:
- identifier: Url
columnName: RequestURL
- entityType: CloudApplication
fieldMappings:
- identifier: Name
columnName: ApplicationProtocol
- entityType: Malware
fieldMappings:
- identifier: Name
columnName: Activity
- identifier: Category
columnName: Rule
version: 1.0.2
kind: Scheduled
Stages and Predicates
Let binding: extract_data
let extract_data = (a:string, k:string) {
parse_urlquery(replace(@';', @'&', a))["Query Parameters"][k]
};
Stage 1: source
CommonSecurityLog
Stage 2: where
| where DeviceVendor == "Contrast Security"
Stage 3: where
| where AdditionalExtensions contains "PROBED" or AdditionalExtensions contains "INEFFECTIVE"
Stage 4: extend (8 consecutive steps)
| extend DeviceProduct
| extend SourceIP
| extend DeviceVersion
| extend Activity
| extend ApplicationProtocol
| extend RequestURL
| extend RequestMethod
| extend Rule = extract_data(AdditionalExtensions, 'pri')
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 |
|---|---|---|
AdditionalExtensions | contains |
|
DeviceVendor | eq |
|
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 |
|---|---|
DeviceProduct | extend |
SourceIP | extend |
DeviceVersion | extend |
Activity | extend |
ApplicationProtocol | extend |
RequestURL | extend |
RequestMethod | extend |
Rule | extend |