CVE-2021-34085
📋 TL;DR
This vulnerability is a read access violation in the III_dequantize_sample function of mp3gain's mpglibDBL library. It allows remote attackers to cause denial of service (application crash) or potentially execute arbitrary code by exploiting improper memory access when processing malicious MP3 files. Anyone using mp3gain versions through 1.5.2-r2 is affected.
💻 Affected Systems
- mp3gain
📦 What is this software?
Mp3gain by Glensawyer
Mp3gain by Glensawyer
Mp3gain by Glensawyer
Mp3gain by Glensawyer
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Application crash causing denial of service for MP3 processing functionality.
If Mitigated
Application crash contained within sandboxed environment with no privilege escalation.
🎯 Exploit Status
Exploitation requires user to process a specially crafted MP3 file. The vulnerability is in a widely used library component.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.5.2-r3 and later
Vendor Advisory: https://sourceforge.net/p/mp3gain/news/
Restart Required: No
Instructions:
1. Download latest version from official source. 2. Uninstall old version. 3. Install new version. 4. Verify installation with version check.
🔧 Temporary Workarounds
Disable MP3 processing
allTemporarily disable or restrict MP3 file processing functionality
Sandbox application
linuxRun mp3gain in isolated container or sandbox environment
docker run --rm -v $(pwd):/data alpine/mp3gain:latest
🧯 If You Can't Patch
- Implement strict file upload validation to block potentially malicious MP3 files
- Run mp3gain with minimal privileges and in isolated environments
🔍 How to Verify
Check if Vulnerable:
Check mp3gain version: mp3gain -v or dpkg -l | grep mp3gainCheck Version:
mp3gain -vVerify Fix Applied:
Verify version is 1.5.2-r3 or higher: mp3gain -v📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation fault
- Memory access violation errors
- Unexpected termination of mp3gain process
Network Indicators:
- Unusual MP3 file uploads to systems
- Multiple failed MP3 processing attempts
SIEM Query:
process_name="mp3gain" AND (event_type="crash" OR exit_code="139")