CVE-2025-66044: The Biosig Project libbiosig · Stack-based Buffer Overflow
Affects The Biosig Project libbiosigSource CVE Database V5
Not known to be exploited · CVSS 9.8 Critical.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 45% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| The Biosig Project libbiosig | Affected
| Fixed in– |
AI-suggested
1. Immediate mitigation should focus on isolating systems that process MFER files using libbiosig 3.9.1 to prevent exposure to untrusted inputs. 2. Implement strict input validation and sanitization for all MFER files before processing, especially checking for Tag values and file integrity. 3. Employ sandboxing or containerization techniques to limit the impact of potential exploitation by isolating the parsing process. 4. Monitor network and system logs for unusual activity related to MFER file handling or unexpected crashes indicative of exploitation attempts. 5. Coordinate with The Biosig Project and relevant vendors for timely patches or updates addressing this vulnerability. 6. Consider deploying intrusion detection/prevention systems (IDS/IPS) with signatures targeting malformed MFER files or buffer overflow patterns. 7. Conduct security awareness training for staff handling biomedical data to recognize suspicious files and report anomalies. 8. Review and strengthen endpoint security controls to detect and block arbitrary code execution attempts. 9. Maintain up-to-date backups of critical biomedical data to enable recovery in case of compromise. 10. Engage in threat intelligence sharing with European cybersecurity communities to stay informed about emerging exploits.
Description
Several stack-based buffer overflow vulnerabilities exists in the MFER parsing functionality of The Biosig Project libbiosig 3.9.1. A specially crafted MFER file can lead to arbitrary code execution. An attacker can provide a malicious file to trigger these vulnerabilities.When Tag is 64