CVE-2025-54489
📋 TL;DR
A stack-based buffer overflow vulnerability in libbiosig's MFER parsing allows arbitrary code execution when processing malicious MFER files. This affects applications using libbiosig 3.9.0 or the master branch to parse biomedical signal files. Attackers can achieve remote code execution by tricking users or systems into opening specially crafted files.
💻 Affected Systems
- The Biosig Project libbiosig
📦 What is this software?
Libbiosig by Libbiosig Project
⚠️ 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 networks.
Likely Case
Remote code execution with the privileges of the application using libbiosig, allowing file system access, data exfiltration, and further malware installation.
If Mitigated
Application crash (denial of service) if exploit attempts fail or are blocked by security controls like ASLR or stack canaries.
🎯 Exploit Status
Exploitation requires the victim to process a malicious MFER file. No authentication is needed if the application accepts external files. The vulnerability is straightforward to exploit due to predictable buffer overflow conditions.
🛠️ 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 website or GitHub repository for patches. 2. Apply the official patch when available. 3. Rebuild and redeploy any applications using libbiosig. 4. Restart affected services.
🔧 Temporary Workarounds
Disable MFER file processing
allTemporarily disable or block MFER file parsing in applications using libbiosig until a patch is available.
Configuration depends on specific application. Check application documentation for disabling specific file format support.
Input validation for MFER files
allImplement strict validation of MFER files before passing to libbiosig, rejecting files with suspicious tag/length combinations.
Custom implementation required based on application.
🧯 If You Can't Patch
- Implement network segmentation to isolate systems using libbiosig from untrusted networks.
- Use application allowlisting to prevent execution of unauthorized binaries that might result from exploitation.
🔍 How to Verify
Check if Vulnerable:
Check libbiosig version: 'biosig_version' command or examine source code for commit hash 35a819fa or version 3.9.0.Check Version:
biosig_version 2>&1 | grep -i versionVerify Fix Applied:
After patching, verify the fixed version is installed and test with known malicious MFER files (in safe environment) to ensure no crashes or unexpected behavior.📡 Detection & Monitoring
Log Indicators:
- Application crashes or abnormal termination when processing MFER files
- Unexpected process spawning or network connections from libbiosig-related processes
Network Indicators:
- Unusual outbound connections from systems running vulnerable libbiosig applications
- File transfers of MFER files from untrusted sources
SIEM Query:
Process: (name="*biosig*" OR command_line="*biosig*") AND (event_type="crash" OR parent_process="unusual")