CVE-2025-46411 identifies a stack-based buffer overflow vulnerability in the MFER parsing component of The Biosig Project's libbiosig library, specifically affecting version 3.9.0 and the master branch (commit 35a819fa). The vulnerability arises due to improper bounds checking when processing specially crafted MFER files, which are used to encode biosignal data such as EEG or ECG recordings. An attacker can exploit this flaw by supplying a maliciously crafted MFER file to an application or service that uses libbiosig for parsing. This leads to a stack buffer overflow, enabling arbitrary code execution with the privileges of the vulnerable process. The vulnerability does not require any user interaction or prior authentication, and the attack vector is network accessible if the application processes MFER files from untrusted sources. The CVSS v3.1 base score of 8.1 reflects the high impact on confidentiality, integrity, and availability, though the attack complexity is high due to the need for crafting a valid malicious MFER file. No patches or fixes are currently linked, indicating that remediation may require vendor updates or custom mitigations. The Biosig Project is commonly used in biomedical research and healthcare applications, making this vulnerability particularly critical in those contexts.

For European organizations, the impact of this vulnerability is significant, especially for those involved in biomedical research, healthcare technology, and biometric data processing. Exploitation could lead to unauthorized code execution, data breaches involving sensitive biosignal data, disruption of critical medical systems, and potential manipulation of diagnostic results. This could compromise patient safety, violate data protection regulations such as GDPR, and result in reputational and financial damage. The vulnerability's ability to affect confidentiality, integrity, and availability simultaneously elevates the risk profile. Organizations relying on libbiosig in clinical environments or research labs may face operational downtime and regulatory scrutiny if exploited. Given the lack of known exploits currently, proactive mitigation is essential to prevent future attacks. The high attack complexity somewhat limits widespread exploitation but does not eliminate the threat, especially from skilled adversaries targeting high-value biomedical assets.

European organizations should immediately audit their use of libbiosig, particularly versions 3.9.0 and the specified master branch, to identify affected systems. Until official patches are released, implement strict input validation and sanitization for all MFER files, rejecting any files from untrusted or unauthenticated sources. Employ runtime protections such as stack canaries, address space layout randomization (ASLR), and control flow integrity (CFI) to reduce exploitation likelihood. Consider sandboxing or isolating processes that parse MFER files to limit potential damage. Monitor system logs and network traffic for unusual activity indicative of exploitation attempts. Engage with The Biosig Project or community to track patch releases and apply updates promptly. For critical healthcare environments, establish incident response plans specific to biosignal data processing systems. Additionally, conduct security awareness training for developers and operators about secure handling of biosignal data and third-party libraries.