CVE-2025-49707
📋 TL;DR
An improper access control vulnerability in Azure Virtual Machines allows authenticated attackers to perform local spoofing attacks. This affects Azure Virtual Machines where an authorized user can exploit the vulnerability to impersonate other entities or processes within the same virtual machine environment.
💻 Affected Systems
- Microsoft Azure Virtual Machines
📦 What is this software?
Dcadsv5 Series Azure Vm Firmware by Microsoft
Dcasv5 Series Azure Vm Firmware by Microsoft
Dcedsv5 Series Azure Vm Firmware by Microsoft
Dcesv5 Series Azure Vm Firmware by Microsoft
Dcesv6 Series Azure Vm Firmware by Microsoft
Ecadsv5 Series Azure Vm Firmware by Microsoft
Ecasv5 Series Azure Vm Firmware by Microsoft
Ecedsv5 Series Azure Vm Firmware by Microsoft
Ecesv5 Series Azure Vm Firmware by Microsoft
Ecesv6 Series Azure Vm Firmware by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
An attacker could escalate privileges, access sensitive data from other users/processes, or manipulate system operations by spoofing legitimate entities within the virtual machine.
Likely Case
Authorized users exploiting the vulnerability to gain unauthorized access to resources or perform actions as other users within the same VM.
If Mitigated
Limited impact with proper access controls, monitoring, and network segmentation in place.
🎯 Exploit Status
Requires authenticated access to the virtual machine; exploitation involves local spoofing techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Azure updates and security bulletins
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-49707
Restart Required: Yes
Instructions:
1. Log into the Azure portal. 2. Navigate to your Virtual Machines. 3. Apply the latest security updates from Microsoft. 4. Restart affected virtual machines as required.
🔧 Temporary Workarounds
Implement strict access controls
allLimit user permissions and implement principle of least privilege within virtual machines
Enable monitoring and logging
allConfigure enhanced logging for authentication and access events within VMs
🧯 If You Can't Patch
- Isolate affected virtual machines from critical resources using network segmentation
- Implement additional authentication controls and monitor for suspicious local activity
🔍 How to Verify
Check if Vulnerable:
Check Azure Security Center for vulnerability assessments or review Microsoft advisory for affected configurationsCheck Version:
For Windows: systeminfo | findstr /B /C:"OS Name" /C:"OS Version" | For Linux: cat /etc/os-releaseVerify Fix Applied:
Verify virtual machines are running the latest Azure updates and security patches📡 Detection & Monitoring
Log Indicators:
- Unusual authentication events
- Privilege escalation attempts
- Suspicious local process impersonation
Network Indicators:
- Unusual internal traffic patterns from virtual machines
SIEM Query:
source="azure-vm-logs" AND (event_type="authentication" OR event_type="privilege_escalation") AND result="failure"