CVE-2025-50164
📋 TL;DR
A heap-based buffer overflow vulnerability in Windows Routing and Remote Access Service (RRAS) allows authenticated attackers to execute arbitrary code remotely. This affects Windows systems with RRAS enabled, potentially compromising network infrastructure. Attackers must have valid credentials to exploit this vulnerability.
💻 Affected Systems
- Windows Routing and Remote Access Service
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with administrative privileges, enabling lateral movement across the network, data exfiltration, and persistent backdoor installation.
Likely Case
Unauthorized code execution with the privileges of the RRAS service account, leading to service disruption, credential theft, and initial foothold for further attacks.
If Mitigated
Limited impact due to network segmentation, strong authentication controls, and monitoring preventing successful exploitation.
🎯 Exploit Status
Requires authenticated access to the RRAS service. Network access to the RRAS port is needed. No public exploit code available at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Security Update for specific KB number
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-50164
Restart Required: Yes
Instructions:
1. Apply the latest Windows security updates from Microsoft. 2. Restart the system to complete the installation. 3. Verify the patch is applied successfully.
🔧 Temporary Workarounds
Disable RRAS Service
windowsTemporarily disable the Routing and Remote Access Service if not required
sc config RemoteAccess start= disabled
net stop RemoteAccess
Network Segmentation
windowsRestrict network access to RRAS service ports using firewall rules
New-NetFirewallRule -DisplayName "Block RRAS" -Direction Inbound -Protocol TCP -LocalPort 1723,1701,47 -Action Block
🧯 If You Can't Patch
- Implement strict network access controls to limit which systems can communicate with RRAS services
- Enforce strong authentication mechanisms and monitor for unusual RRAS authentication attempts
🔍 How to Verify
Check if Vulnerable:
Check if RRAS service is running and compare Windows version against affected versions in Microsoft advisoryCheck Version:
systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify Windows Update history shows the relevant security update installed and RRAS service is still functional📡 Detection & Monitoring
Log Indicators:
- Unusual RRAS service crashes or restarts
- Failed authentication attempts followed by successful authentication
- Unusual process creation from RRAS service context
Network Indicators:
- Unusual network traffic patterns to RRAS ports (1723, 1701, 47)
- Multiple authentication attempts from single source
SIEM Query:
source="windows" AND (event_id=4625 OR event_id=4688) AND process_name="svchost.exe" AND service_name="RemoteAccess"