Detection rules › Kusto

Cisco Duo - Multiple user login failures

Status
available
Severity
high
Time window
10m
Group by
DstUserName
Source
github.com/Azure/Azure-Sentinel

'Detects when multiple user login failures occurs.'

MITRE ATT&CK coverage

TacticTechniques
Initial AccessT1078 Valid Accounts

Rule body kusto

id: 034f62b6-df51-49f3-831f-1e4cfd3c40d2
name: Cisco Duo - Multiple user login failures
description: |
  'Detects when multiple user login failures occurs.'
severity: High
status: Available
requiredDataConnectors:
  - connectorId: CiscoDuoSecurity
    dataTypes:
      - CiscoDuo
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
relevantTechniques:
  - T1078
query: |
  let threshold = 10;
  CiscoDuo
  | where EventType =~ 'authentication'
  | where EventResult in~ ('denied', 'failure')
  | summarize count() by DstUserName, bin(TimeGenerated, 10m)
  | where count_ > threshold
  | extend AccountCustomEntity = DstUserName
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: AccountCustomEntity
version: 1.0.1
kind: Scheduled

Stages and Predicates

Parameters

let threshold = 10;

Stage 1: source

CiscoDuo

Stage 2: where

| where EventType =~ 'authentication'

Stage 3: where

| where EventResult in~ ('denied', 'failure')

Stage 4: summarize

| summarize count() by DstUserName, bin(TimeGenerated, 10m)

Stage 5: where

| where count_ > threshold

Stage 6: extend

| extend AccountCustomEntity = DstUserName

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
EventResultin
  • denied
  • failure
EventTypeeq
  • authentication
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
DstUserNamesummarize
AccountCustomEntityextend