CVE-2020-24020
📋 TL;DR
This CVE describes a buffer overflow vulnerability in FFmpeg's DNN module that allows remote attackers to execute arbitrary code by exploiting improper memory bounds checking in the pad layer function. It affects systems running FFmpeg 4.2.3 that process untrusted media files. The vulnerability is particularly dangerous for media processing servers and applications that handle user-uploaded content.
💻 Affected Systems
- FFmpeg
📦 What is this software?
Ffmpeg by Ffmpeg
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the privileges of the FFmpeg process, potentially leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Remote code execution leading to service disruption, data exfiltration, or lateral movement within the network.
If Mitigated
Denial of service if exploit fails or is blocked by security controls, with potential application crashes.
🎯 Exploit Status
Exploitation requires crafting a malicious media file that triggers the vulnerable DNN pad layer function.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FFmpeg 4.2.4 and later
Vendor Advisory: https://trac.ffmpeg.org/ticket/8718
Restart Required: Yes
Instructions:
1. Update FFmpeg to version 4.2.4 or later. 2. Rebuild any applications using FFmpeg libraries. 3. Restart affected services.
🔧 Temporary Workarounds
Disable DNN processing
allDisable DNN-based filters and features in FFmpeg configuration
Configure FFmpeg with --disable-dnn or avoid using DNN-related filters
Input validation
allImplement strict input validation for media files before processing
🧯 If You Can't Patch
- Implement network segmentation to isolate FFmpeg processing systems
- Deploy application allowlisting to prevent execution of unauthorized code
🔍 How to Verify
Check if Vulnerable:
Check FFmpeg version: ffmpeg -version | grep 'version'Check Version:
ffmpeg -version | grep 'version'Verify Fix Applied:
Verify version is 4.2.4 or later and check commit history for fix 584f396132aa19d21bb1e38ad9a5d428869290cb📡 Detection & Monitoring
Log Indicators:
- FFmpeg process crashes
- Memory access violation errors
- Unusual process spawning from FFmpeg
Network Indicators:
- Unexpected outbound connections from media processing servers
- Large media file uploads to processing endpoints
SIEM Query:
Process:ffmpeg AND (EventID:1000 OR ExceptionCode:c0000005)