Cyber Posture

CVE-2025-66044

CriticalPublic PoC

Published: 11 December 2025

Published
11 December 2025
Modified
17 December 2025
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0019 40.7th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

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…

more

is 64

Mitigating Controls (NIST 800-53 r5)AI

prevent

Flaw remediation directly mitigates the CVE by requiring timely patching of the buffer overflow vulnerability in libbiosig 3.9.1.

prevent

Information input validation prevents exploitation by ensuring proper validation of specially crafted MFER files during parsing, addressing the root cause of the stack-based buffer overflows.

prevent

Memory protection mechanisms like stack canaries, ASLR, and DEP directly mitigate stack-based buffer overflows by preventing arbitrary code execution even if overflows occur.

Security SummaryAI

CVE-2025-66044 involves several stack-based buffer overflow vulnerabilities (CWE-121 and CWE-787) in the MFER parsing functionality of The Biosig Project's libbiosig version 3.9.1. These issues arise when processing a specially crafted MFER file, particularly when the Tag value is 64, and can lead to arbitrary code execution.

The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), making it remotely exploitable over a network with low attack complexity, no required privileges or user interaction, and high impacts on confidentiality, integrity, and availability. Any attacker capable of providing a malicious MFER file to an application or system using the affected libbiosig version can trigger the overflows to achieve arbitrary code execution on the target.

Mitigation details are outlined in the Talos Intelligence advisory TALOS-2025-2296, available at https://talosintelligence.com/vulnerability_reports/TALOS-2025-2296.

Details

CWE(s)

Affected Products

libbiosig project
libbiosig
≤ 3.9.2

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

The vulnerability enables remote arbitrary code execution (AV:N/AC:L/PR:N/UI:N) via a crafted MFER file in applications using libbiosig, directly mapping to exploitation of public-facing applications.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References