GitLab - User Impersonation

let impersonationStart = (GitLabAudit
| where CustomMessage == 'Started Impersonation');
let impersonationStop = (GitLabAudit
| where CustomMessage == 'Stopped Impersonation');
impersonationStart
| join kind=inner impersonationStop on $left.TargetID == $right.TargetID and $left.AuthorID == $right.AuthorID 
| where EventTime1 > EventTime
| extend TimeGenerated, AuthorID, AuthorName, TargetID, TargetDetails = TargetDetails, IPStart = IPAddress, IPStop = IPAddress1, ImpStartTime = EventTime, ImpStopTime = EventTime1, EntityName
| join kind=inner (GitLabAudit | extend ActionTime = EventTime, AuthorName) on $left.TargetDetails == $right.AuthorName 
| where ImpStartTime < ActionTime and ActionTime > ImpStopTime

severity: Medium
relevantTechniques:
- T1078
queryFrequency: 1h
kind: Scheduled
version: 1.0.1
name: GitLab - User Impersonation
triggerOperator: gt
description: |
    'This queries GitLab Audit Logs for user impersonation. A malicious operator or a compromised admin account could leverage the impersonation feature of GitLab to change code or repository settings bypassing usual processes. This hunting queries allows you to track the audit actions done under impersonation.'
queryPeriod: 1d
query: |
  let impersonationStart = (GitLabAudit
  | where CustomMessage == 'Started Impersonation');
  let impersonationStop = (GitLabAudit
  | where CustomMessage == 'Stopped Impersonation');
  impersonationStart
  | join kind=inner impersonationStop on $left.TargetID == $right.TargetID and $left.AuthorID == $right.AuthorID 
  | where EventTime1 > EventTime
  | extend TimeGenerated, AuthorID, AuthorName, TargetID, TargetDetails = TargetDetails, IPStart = IPAddress, IPStop = IPAddress1, ImpStartTime = EventTime, ImpStopTime = EventTime1, EntityName
  | join kind=inner (GitLabAudit | extend ActionTime = EventTime, AuthorName) on $left.TargetDetails == $right.AuthorName 
  | where ImpStartTime < ActionTime and ActionTime > ImpStopTime  
entityMappings:
- entityType: IP
  fieldMappings:
  - columnName: IPStart
    identifier: Address
- entityType: IP
  fieldMappings:
  - columnName: IPStop
    identifier: Address
- entityType: Account
  fieldMappings:
  - columnName: EntityName
    identifier: FullName
- entityType: Account
  fieldMappings:
  - columnName: TargetDetails
    identifier: FullName
tactics:
- Persistence
status: Available
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GitLab/Analytic Rules/GitLab_Impersonation.yaml
id: 0f4f16a2-b464-4c10-9a42-993da3e15a40
requiredDataConnectors:
- dataTypes:
  - Syslog
  connectorId: Syslog

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/0f4f16a2-b464-4c10-9a42-993da3e15a40')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/0f4f16a2-b464-4c10-9a42-993da3e15a40')]",
      "properties": {
        "alertRuleTemplateName": "0f4f16a2-b464-4c10-9a42-993da3e15a40",
        "customDetails": null,
        "description": "'This queries GitLab Audit Logs for user impersonation. A malicious operator or a compromised admin account could leverage the impersonation feature of GitLab to change code or repository settings bypassing usual processes. This hunting queries allows you to track the audit actions done under impersonation.'\n",
        "displayName": "GitLab - User Impersonation",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPStart",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPStop",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "EntityName",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "TargetDetails",
                "identifier": "FullName"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GitLab/Analytic Rules/GitLab_Impersonation.yaml",
        "query": "let impersonationStart = (GitLabAudit\n| where CustomMessage == 'Started Impersonation');\nlet impersonationStop = (GitLabAudit\n| where CustomMessage == 'Stopped Impersonation');\nimpersonationStart\n| join kind=inner impersonationStop on $left.TargetID == $right.TargetID and $left.AuthorID == $right.AuthorID \n| where EventTime1 > EventTime\n| extend TimeGenerated, AuthorID, AuthorName, TargetID, TargetDetails = TargetDetails, IPStart = IPAddress, IPStop = IPAddress1, ImpStartTime = EventTime, ImpStopTime = EventTime1, EntityName\n| join kind=inner (GitLabAudit | extend ActionTime = EventTime, AuthorName) on $left.TargetDetails == $right.AuthorName \n| where ImpStartTime < ActionTime and ActionTime > ImpStopTime\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence"
        ],
        "techniques": [
          "T1078"
        ],
        "templateVersion": "1.0.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}