Detection rules › Kusto

Palo Alto Prisma Cloud - Anomalous access key usage

Status
available
Severity
medium
Time window
5m
Group by
UserName
Source
github.com/Azure/Azure-Sentinel

'Detects anomalous API key usage activity.'

MITRE ATT&CK coverage

TacticTechniques
Initial AccessT1078 Valid Accounts

Rule body kusto

id: bd602b90-f7f9-4ae9-bf8c-3672a24deb39
name: Palo Alto Prisma Cloud - Anomalous access key usage
description: |
  'Detects anomalous API key usage activity.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: PaloAltoPrismaCloud
    dataTypes:
      - PaloAltoPrismaCloud
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
relevantTechniques:
  - T1078
query: |
  let threshold = 10;
  PaloAltoPrismaCloud
  | where ResourceType =~ 'Login'
  | where EventResult =~ 'Failed'
  | where EventMessage has 'access key'
  | summarize count() by UserName, bin(TimeGenerated, 5m)
  | where count_ > threshold
  | extend AccountCustomEntity = UserName
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: AccountCustomEntity
version: 1.0.1
kind: Scheduled

Stages and Predicates

Parameters

let threshold = 10;

Stage 1: source

PaloAltoPrismaCloud

Stage 2: where

| where ResourceType =~ 'Login'

Stage 3: where

| where EventResult =~ 'Failed'

Stage 4: where

| where EventMessage has 'access key'

Stage 5: summarize

| summarize count() by UserName, bin(TimeGenerated, 5m)

Stage 6: where

| where count_ > threshold

Stage 7: extend

| extend AccountCustomEntity = UserName

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.

FieldKindValues
EventMessagematch
  • access key transforms: term
EventResulteq
  • Failed
ResourceTypeeq
  • Login
count_gt
  • 10 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.

FieldSource
UserNamesummarize
AccountCustomEntityextend