CVE-2025-29813
📋 TL;DR
CVE-2025-29813 is an authentication bypass vulnerability in Azure DevOps that allows attackers to spoof identity claims and gain unauthorized access. Attackers can elevate privileges by manipulating assumed-immutable authentication data. This affects organizations using Azure DevOps services.
💻 Affected Systems
- Azure DevOps Services
- Azure DevOps Server
📦 What is this software?
Azure Devops by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of Azure DevOps organization with administrative access to all projects, repositories, pipelines, and sensitive data.
Likely Case
Unauthorized access to source code, build pipelines, and project data leading to intellectual property theft or supply chain attacks.
If Mitigated
Limited impact if multi-factor authentication and strict access controls are enforced, though authentication bypass remains possible.
🎯 Exploit Status
Exploitation requires understanding of Azure DevOps authentication mechanisms but no authentication needed to initiate attack.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Security Update Guide for specific versions
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-29813
Restart Required: Yes
Instructions:
1. For Azure DevOps Services: Microsoft will apply patches automatically
2. For Azure DevOps Server: Download and apply latest security updates from Microsoft Update
3. Restart Azure DevOps services after patch installation
4. Verify authentication mechanisms are functioning correctly
🔧 Temporary Workarounds
Network Segmentation
allRestrict access to Azure DevOps to trusted networks only
Enhanced Monitoring
allImplement strict monitoring of authentication events and privilege changes
🧯 If You Can't Patch
- Implement network-level access controls to restrict Azure DevOps access to minimum necessary IP ranges
- Enable detailed audit logging for all authentication events and regularly review for suspicious activity
🔍 How to Verify
Check if Vulnerable:
Check Azure DevOps version against Microsoft security bulletin. For Azure DevOps Services, verify Microsoft has applied updates.Check Version:
For Azure DevOps Server: Check version in administration console or via PowerShell: Get-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\Azure DevOps'Verify Fix Applied:
Test authentication flows with various user roles and verify proper access controls are enforced. Check that identity claims cannot be manipulated.📡 Detection & Monitoring
Log Indicators:
- Unusual authentication patterns
- Privilege escalation events
- Access from unexpected locations or IPs
- Failed authentication attempts followed by successful access
Network Indicators:
- Unusual authentication traffic patterns
- Requests manipulating identity tokens or claims
SIEM Query:
source="azure-devops" AND (event_type="authentication" OR event_type="authorization") AND (result="success" FROM previously_failed_ip) OR (privilege_change="elevated")