Detection rules › Kusto

User Accessed Suspicious URL Categories

Status
available
Severity
medium
Time window
1h
Group by
Computer, c_ip, cs_host, cs_userdn, sc_filter_result
Source
github.com/Azure/Azure-Sentinel

'Creates an incident in the event the requested URL accessed by the user has been identified as Suspicious, Phishing, or Hacking.'

MITRE ATT&CK coverage

TacticTechniques
Initial AccessT1566 Phishing
Command & ControlT1071 Application Layer Protocol

Rule body kusto

id: fb0f4a93-d8ad-4b54-9931-85bdb7550f90
name: User Accessed Suspicious URL Categories
description: |
  'Creates an incident in the event the requested URL accessed by the user has been identified as Suspicious, Phishing, or Hacking.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: SyslogAma
    datatypes:
      - Syslog
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
  - CommandAndControl
relevantTechniques:
  - T1566
  - T1071
query: |
  SymantecProxySG
  | mv-expand cs_categories
  | where cs_categories has_any ("Suspicious","phishing", "hacking")
  | summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), count() by sc_filter_result, cs_userdn, c_ip, cs_host, Computer,  tostring(cs_categories)
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: cs_userdn
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: Computer
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: c_ip
version: 1.0.5
kind: Scheduled

Stages and Predicates

Stage 1: source

SymantecProxySG

Stage 2: mv-expand

| mv-expand cs_categories

Stage 3: where

| where cs_categories has_any ("Suspicious","phishing", "hacking")

Stage 4: summarize

| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), count() by sc_filter_result, cs_userdn, c_ip, cs_host, Computer,  tostring(cs_categories)

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
cs_categoriesmatch
  • Suspicious
  • hacking
  • phishing

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
Computersummarize
EndTimesummarize
StartTimesummarize
c_ipsummarize
cs_hostsummarize
cs_userdnsummarize
sc_filter_resultsummarize