CVE-2021-32271
📋 TL;DR
This vulnerability is a stack buffer overflow in GPAC's DumpRawUIConfig function that allows remote code execution when processing malicious files. Attackers can exploit this by tricking users into opening specially crafted media files. Anyone using vulnerable versions of GPAC is affected.
💻 Affected Systems
- GPAC Multimedia Framework
📦 What is this software?
Gpac by Gpac
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining complete control over the affected system, potentially leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Local privilege escalation or remote code execution when processing malicious media files, resulting in malware installation or system disruption.
If Mitigated
Denial of service or application crash if exploit fails, with minimal impact if proper sandboxing and privilege separation are implemented.
🎯 Exploit Status
Exploitation requires user interaction to open malicious files. The vulnerability is in a core parsing function making reliable exploitation feasible.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after commit 5b6c1a5 (2021-03-22)
Vendor Advisory: https://github.com/gpac/gpac/issues/1575
Restart Required: Yes
Instructions:
1. Update GPAC to version after commit 5b6c1a5. 2. Rebuild from source or use updated package. 3. Restart any services using GPAC. 4. Verify the fix with test files.
🔧 Temporary Workarounds
Disable vulnerable component
linuxRemove or disable GPAC if not essential for operations
sudo apt remove gpac
sudo yum remove gpac
Input validation
allImplement strict file type validation before processing with GPAC
🧯 If You Can't Patch
- Implement application sandboxing to limit damage from successful exploitation
- Use network segmentation to isolate systems running vulnerable GPAC versions
🔍 How to Verify
Check if Vulnerable:
Check GPAC version: gpac -version. If version date is 20200801 or earlier, you are vulnerable.Check Version:
gpac -version 2>&1 | head -1Verify Fix Applied:
Test with known malicious test files or verify version is after commit 5b6c1a5.📡 Detection & Monitoring
Log Indicators:
- GPAC process crashes
- Memory access violation errors
- Unusual file processing patterns
Network Indicators:
- Unexpected outbound connections from GPAC processes
- File downloads followed by GPAC execution
SIEM Query:
process_name:gpac AND (event_id:1000 OR event_id:1001) OR process_name:gpac AND network_connection:established