CVE-2025-8585
📋 TL;DR
A critical double-free vulnerability in libav's DSS File Demuxer component allows local attackers to potentially execute arbitrary code or cause denial of service. This affects libav versions up to 12.3, but only impacts products that are no longer supported by maintainers.
💻 Affected Systems
- libav
📦 What is this software?
Libav by Libav
⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation leading to full system compromise via arbitrary code execution
Likely Case
Application crash causing denial of service for the affected process
If Mitigated
Limited impact due to local-only attack vector and unsupported software status
🎯 Exploit Status
Exploit requires local access and manipulation of DSS files through avconv tool
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: N/A
Vendor Advisory: N/A
Restart Required: No
Instructions:
No official patch available as libav is no longer maintained. Migrate to FFmpeg or alternative supported media libraries.
🔧 Temporary Workarounds
Disable DSS File Demuxer
allRemove or disable the vulnerable DSS file format support
Recompile libav without DSS demuxer support
Restrict avconv usage
Linux/UnixLimit execution of avconv tool to trusted users only
chmod 750 /usr/bin/avconv
setfacl -m u:trusteduser:rx /usr/bin/avconv
🧯 If You Can't Patch
- Migrate to FFmpeg or other actively maintained media processing libraries
- Implement strict access controls to limit who can execute avconv on affected systems
🔍 How to Verify
Check if Vulnerable:
Check libav version: avconv -version | grep 'libav version'Check Version:
avconv -version | grep 'libav version'Verify Fix Applied:
Verify migration to FFmpeg or removal of vulnerable libav installation📡 Detection & Monitoring
Log Indicators:
- Segmentation fault or crash logs from avconv process
- Unusual avconv execution patterns
Network Indicators:
- N/A - local-only vulnerability
SIEM Query:
Process:avconv AND (EventID:1000 OR Signal:SIGSEGV)