CVE-2026-26117
📋 TL;DR
This vulnerability allows an authenticated attacker to bypass authentication mechanisms in Azure Windows Virtual Machine Agent, enabling local privilege escalation. It affects Azure Windows Virtual Machines running the vulnerable agent version. Attackers must already have some level of access to the system to exploit this flaw.
💻 Affected Systems
- Azure Windows Virtual Machine Agent
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise where an authenticated attacker gains SYSTEM/administrator privileges, potentially leading to data theft, lateral movement, or complete control of the virtual machine.
Likely Case
Local privilege escalation allowing attackers to bypass security controls, install malware, or access restricted resources within the compromised virtual machine.
If Mitigated
Limited impact due to proper access controls, network segmentation, and monitoring preventing successful exploitation or containing the damage.
🎯 Exploit Status
Requires authenticated access to the system. Exploitation likely involves manipulating authentication paths or channels within the agent.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Security Update Guide for specific version
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26117
Restart Required: Yes
Instructions:
1. Access Azure Portal
2. Navigate to affected Windows VMs
3. Apply latest Windows updates
4. Restart virtual machines
5. Verify agent version is updated
🔧 Temporary Workarounds
Restrict local access
windowsLimit user accounts with local access to Azure Windows VMs to reduce attack surface
Network segmentation
allIsolate vulnerable VMs in restricted network segments to limit lateral movement
🧯 If You Can't Patch
- Implement strict access controls and least privilege principles for all user accounts
- Enable enhanced monitoring and alerting for privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check Azure VM agent version against Microsoft's advisory for vulnerable versionsCheck Version:
Get-WmiObject -Class Win32_Product | Where-Object {$_.Name -like '*Azure*Agent*'} | Select-Object Name, VersionVerify Fix Applied:
Verify agent version has been updated to patched version and restart has been completed📡 Detection & Monitoring
Log Indicators:
- Unusual authentication events in Windows Security logs
- Privilege escalation attempts
- Unexpected process execution with elevated privileges
Network Indicators:
- Unusual outbound connections from Azure VMs post-exploitation
- Lateral movement attempts to other systems
SIEM Query:
EventID=4672 OR EventID=4688 | where ProcessName contains 'agent' AND SubjectUserName != System