CVE-2022-30976
📋 TL;DR
CVE-2022-30976 is a heap-based buffer over-read vulnerability in GPAC's Unicode handling function. Attackers can exploit this by crafting malicious MP4 files to cause memory corruption, potentially leading to information disclosure or denial of service. Users of GPAC 2.0.0 and MP4Box are affected.
💻 Affected Systems
- GPAC
- MP4Box
📦 What is this software?
Gpac by Gpac
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, though this requires specific memory layout conditions.
Likely Case
Application crash (denial of service) or information disclosure from heap memory.
If Mitigated
Application crash with no further impact if memory protections are enabled.
🎯 Exploit Status
Exploitation requires crafting malicious MP4 files. The GitHub issue shows proof-of-concept discussion.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: GPAC 2.1.0 or later
Vendor Advisory: https://github.com/gpac/gpac/issues/2179
Restart Required: Yes
Instructions:
1. Update GPAC to version 2.1.0 or later. 2. Recompile from source if using custom builds. 3. Restart any services using GPAC/MP4Box.
🔧 Temporary Workarounds
Disable MP4Box processing
linuxTemporarily disable or restrict MP4Box usage until patching.
sudo systemctl stop mp4box-service
sudo chmod 000 /usr/bin/MP4Box
Input validation
allImplement strict validation of MP4 files before processing.
🧯 If You Can't Patch
- Implement network segmentation to isolate GPAC systems
- Use application allowlisting to prevent unauthorized GPAC execution
🔍 How to Verify
Check if Vulnerable:
Check GPAC version: gpac -version or MP4Box -version. If output shows 2.0.0, system is vulnerable.Check Version:
gpac -version 2>&1 | head -1Verify Fix Applied:
After update, verify version shows 2.1.0 or later. Test with known malicious MP4 files to ensure no crashes.📡 Detection & Monitoring
Log Indicators:
- GPAC/MP4Box segmentation faults
- Memory access violation errors in system logs
- Unexpected process termination
Network Indicators:
- Unusual MP4 file transfers to GPAC systems
- Multiple failed processing attempts
SIEM Query:
process_name:"MP4Box" AND (event_type:"crash" OR exit_code:139)🔗 References
- https://github.com/gpac/gpac/blob/105d67985ff3c3f4b98a98f312e3d84ae77a4463/share/doc/man/gpac.1#L2226-L2229
- https://github.com/gpac/gpac/blob/105d67985ff3c3f4b98a98f312e3d84ae77a4463/src/utils/utf.c#L35-L59
- https://github.com/gpac/gpac/issues/2179
- https://github.com/gpac/gpac/blob/105d67985ff3c3f4b98a98f312e3d84ae77a4463/share/doc/man/gpac.1#L2226-L2229
- https://github.com/gpac/gpac/blob/105d67985ff3c3f4b98a98f312e3d84ae77a4463/src/utils/utf.c#L35-L59
- https://github.com/gpac/gpac/issues/2179
