CVE-2025-54491
📋 TL;DR
A critical stack-based buffer overflow vulnerability in libbiosig's MFER parsing allows arbitrary code execution when processing malicious MFER files. This affects libbiosig 3.9.0 and the master branch (35a819fa), potentially impacting any application or system using this library for medical signal file processing.
💻 Affected Systems
- The Biosig Project libbiosig
📦 What is this software?
Libbiosig by Libbiosig Project
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with remote code execution leading to data theft, ransomware deployment, or complete system takeover.
Likely Case
Arbitrary code execution with the privileges of the application using libbiosig, potentially leading to data exfiltration or lateral movement.
If Mitigated
Denial of service or application crash if exploit fails or is blocked by security controls.
🎯 Exploit Status
Exploitation requires only a malicious MFER file to be processed by vulnerable software. No authentication or user interaction beyond file processing is needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not yet released
Vendor Advisory: https://talosintelligence.com/vulnerability_reports/TALOS-2025-2234
Restart Required: Yes
Instructions:
1. Monitor The Biosig Project for official patch release. 2. Apply patch when available. 3. Rebuild and redeploy any applications using libbiosig. 4. Restart affected services.
🔧 Temporary Workarounds
Disable MFER file processing
allConfigure applications to reject or not process MFER files if not required.
Input validation and sanitization
allImplement strict validation of MFER files before passing to libbiosig.
🧯 If You Can't Patch
- Isolate systems using libbiosig in network segments with strict access controls.
- Implement application allowlisting to prevent execution of unauthorized code.
🔍 How to Verify
Check if Vulnerable:
Check libbiosig version: biosig-tools --version or examine source code for version 3.9.0 or commit 35a819fa.Check Version:
biosig-tools --version 2>/dev/null || echo "Check application dependencies for libbiosig version"Verify Fix Applied:
Verify updated libbiosig version after patch is released and confirm MFER parsing functionality is secure.📡 Detection & Monitoring
Log Indicators:
- Application crashes when processing MFER files
- Unusual process execution from applications using libbiosig
Network Indicators:
- Unexpected network connections from applications after processing MFER files
SIEM Query:
source="application_logs" AND ("libbiosig" OR "MFER") AND ("crash" OR "segfault" OR "buffer overflow")