CVE-2026-22852
📋 TL;DR
A heap buffer overflow vulnerability in FreeRDP allows malicious RDP servers to trigger memory corruption and crash FreeRDP clients. This affects all FreeRDP clients connecting to untrusted RDP servers. The vulnerability is in the audio input processing code when handling format lists.
💻 Affected Systems
- FreeRDP
📦 What is this software?
Freerdp by Freerdp
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise of the FreeRDP client machine.
Likely Case
Client crash and denial of service, potentially allowing attackers to disrupt RDP sessions.
If Mitigated
Limited to denial of service if exploit fails to achieve code execution.
🎯 Exploit Status
Exploitation requires the client to connect to a malicious RDP server. No authentication is needed to trigger the vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.20.1
Vendor Advisory: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9chc-g79v-4qq4
Restart Required: Yes
Instructions:
1. Download FreeRDP 3.20.1 or later from the official repository. 2. Compile and install the new version. 3. Restart any FreeRDP client applications.
🔧 Temporary Workarounds
Disable Audio Input
allDisable audio input functionality in FreeRDP client configuration to prevent triggering the vulnerable code path.
xfreerdp /audio-input:off /v:server
🧯 If You Can't Patch
- Restrict RDP connections to trusted servers only using network controls.
- Monitor for crashes of FreeRDP processes and investigate connections preceding crashes.
🔍 How to Verify
Check if Vulnerable:
Check FreeRDP version with 'xfreerdp --version' or equivalent command. If version is below 3.20.1, the system is vulnerable.Check Version:
xfreerdp --versionVerify Fix Applied:
Verify the installed version is 3.20.1 or higher using the version check command.📡 Detection & Monitoring
Log Indicators:
- FreeRDP process crashes
- Segmentation fault errors in system logs
Network Indicators:
- RDP connections to untrusted servers
- Multiple failed RDP sessions
SIEM Query:
process.name:"xfreerdp" AND event.action:"crashed"