Azure DevOps Pull Request Policy Bypassing - Historic allow list

let starttime = 14d;
let endtime = 3h;
// Add full UPN (user@domain.com) to Authorized Bypassers to ignore policy bypasses by certain authorized users
let AuthorizedBypassers = dynamic(['foo@baz.com', 'test@foo.com']);
let historicBypassers = ADOAuditLogs
| where TimeGenerated between (ago(starttime) .. ago(endtime))
| where OperationName == 'Git.RefUpdatePoliciesBypassed'
| distinct ActorUPN;
ADOAuditLogs
| where TimeGenerated >= ago(endtime)
| where OperationName == 'Git.RefUpdatePoliciesBypassed'
| where ActorUPN !in (historicBypassers) and ActorUPN !in (AuthorizedBypassers)
| parse ScopeDisplayName with OrganizationName '(Organization)'
| project TimeGenerated, ActorUPN, IpAddress, UserAgent, OrganizationName, ProjectName, RepoName = Data.RepoName, AlertDetails = Details, Branch = Data.Name,
  BypassReason = Data.BypassReason, PRLink = strcat('https://dev.azure.com/', OrganizationName, '/', ProjectName, '/_git/', Data.RepoName, '/pullrequest/', Data.PullRequestId)
| extend timestamp = TimeGenerated
| extend AccountName = tostring(split(ActorUPN, "@")[0]), AccountUPNSuffix = tostring(split(ActorUPN, "@")[1])

queryFrequency: 3h
requiredDataConnectors: []
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/AzureDevOpsAuditing/Analytic Rules/AzDOHistoricPrPolicyBypassing.yaml
query: |
  let starttime = 14d;
  let endtime = 3h;
  // Add full UPN (user@domain.com) to Authorized Bypassers to ignore policy bypasses by certain authorized users
  let AuthorizedBypassers = dynamic(['foo@baz.com', 'test@foo.com']);
  let historicBypassers = ADOAuditLogs
  | where TimeGenerated between (ago(starttime) .. ago(endtime))
  | where OperationName == 'Git.RefUpdatePoliciesBypassed'
  | distinct ActorUPN;
  ADOAuditLogs
  | where TimeGenerated >= ago(endtime)
  | where OperationName == 'Git.RefUpdatePoliciesBypassed'
  | where ActorUPN !in (historicBypassers) and ActorUPN !in (AuthorizedBypassers)
  | parse ScopeDisplayName with OrganizationName '(Organization)'
  | project TimeGenerated, ActorUPN, IpAddress, UserAgent, OrganizationName, ProjectName, RepoName = Data.RepoName, AlertDetails = Details, Branch = Data.Name,
    BypassReason = Data.BypassReason, PRLink = strcat('https://dev.azure.com/', OrganizationName, '/', ProjectName, '/_git/', Data.RepoName, '/pullrequest/', Data.PullRequestId)
  | extend timestamp = TimeGenerated
  | extend AccountName = tostring(split(ActorUPN, "@")[0]), AccountUPNSuffix = tostring(split(ActorUPN, "@")[1])  
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: ActorUPN
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: IpAddress
- entityType: URL
  fieldMappings:
  - identifier: Url
    columnName: PRLink
relevantTechniques:
- T1098
name: Azure DevOps Pull Request Policy Bypassing - Historic allow list
description: |
    'This detection builds an allow list of historic PR policy bypasses and compares to recent history, flagging pull request bypasses that are not manually in the allow list and not historically included in the allow list.'
severity: Medium
queryPeriod: 14d
triggerOperator: gt
kind: Scheduled
status: Available
tactics:
- Persistence
id: 4d8de9e6-263e-4845-8618-cd23a4f58b70
version: 1.0.6
triggerThreshold: 0

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/4d8de9e6-263e-4845-8618-cd23a4f58b70')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4d8de9e6-263e-4845-8618-cd23a4f58b70')]",
      "properties": {
        "alertRuleTemplateName": "4d8de9e6-263e-4845-8618-cd23a4f58b70",
        "customDetails": null,
        "description": "'This detection builds an allow list of historic PR policy bypasses and compares to recent history, flagging pull request bypasses that are not manually in the allow list and not historically included in the allow list.'\n",
        "displayName": "Azure DevOps Pull Request Policy Bypassing - Historic allow list",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "ActorUPN",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IpAddress",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "PRLink",
                "identifier": "Url"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/AzureDevOpsAuditing/Analytic Rules/AzDOHistoricPrPolicyBypassing.yaml",
        "query": "let starttime = 14d;\nlet endtime = 3h;\n// Add full UPN (user@domain.com) to Authorized Bypassers to ignore policy bypasses by certain authorized users\nlet AuthorizedBypassers = dynamic(['foo@baz.com', 'test@foo.com']);\nlet historicBypassers = ADOAuditLogs\n| where TimeGenerated between (ago(starttime) .. ago(endtime))\n| where OperationName == 'Git.RefUpdatePoliciesBypassed'\n| distinct ActorUPN;\nADOAuditLogs\n| where TimeGenerated >= ago(endtime)\n| where OperationName == 'Git.RefUpdatePoliciesBypassed'\n| where ActorUPN !in (historicBypassers) and ActorUPN !in (AuthorizedBypassers)\n| parse ScopeDisplayName with OrganizationName '(Organization)'\n| project TimeGenerated, ActorUPN, IpAddress, UserAgent, OrganizationName, ProjectName, RepoName = Data.RepoName, AlertDetails = Details, Branch = Data.Name,\n  BypassReason = Data.BypassReason, PRLink = strcat('https://dev.azure.com/', OrganizationName, '/', ProjectName, '/_git/', Data.RepoName, '/pullrequest/', Data.PullRequestId)\n| extend timestamp = TimeGenerated\n| extend AccountName = tostring(split(ActorUPN, \"@\")[0]), AccountUPNSuffix = tostring(split(ActorUPN, \"@\")[1])\n",
        "queryFrequency": "PT3H",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence"
        ],
        "techniques": [
          "T1098"
        ],
        "templateVersion": "1.0.6",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}