CVE-2025-46411 is a high-severity stack-based buffer overflow vulnerability identified in The Biosig Project's libbiosig library, specifically affecting version 3.9.0 and the Master Branch (commit 35a819fa). The vulnerability resides in the MFER (Multi-Format Electroencephalogram Recording) file parsing functionality. A stack-based buffer overflow occurs when the library processes a specially crafted MFER file, allowing an attacker to overwrite the stack memory. This can lead to arbitrary code execution without requiring any user interaction or authentication. The vulnerability has a CVSS v3.1 base score of 8.1, reflecting its network attack vector (AV:N), high attack complexity (AC:H), no privileges required (PR:N), no user interaction (UI:N), and high impact on confidentiality, integrity, and availability (C:H/I:H/A:H). Although no known exploits are currently reported in the wild, the potential for remote exploitation exists if an attacker can supply a malicious MFER file to a vulnerable system using libbiosig for EEG data processing. The lack of available patches at the time of publication increases the urgency for mitigation. The vulnerability is classified under CWE-121, indicating a classic stack-based buffer overflow issue, which is a common and critical memory corruption flaw that can be exploited to execute arbitrary code or cause denial of service.

For European organizations, especially those in healthcare, neuroscience research, and medical device manufacturing, this vulnerability poses significant risks. Libbiosig is used in software that processes biosignal data such as EEG recordings, which are critical for diagnostics and research. Exploitation could lead to unauthorized code execution on systems handling sensitive patient data, potentially compromising confidentiality and integrity of medical records and research data. This could disrupt clinical workflows, damage trust in medical devices and software, and lead to regulatory non-compliance under GDPR due to data breaches. Additionally, compromised systems could be leveraged as footholds for further lateral movement within networks, amplifying the impact. The high severity and remote exploitability without user interaction make this a critical concern for organizations relying on biosignal processing tools.

European organizations should immediately inventory their use of libbiosig, particularly versions 3.9.0 and the specified master branch. Until an official patch is released, organizations should implement strict input validation and sandboxing for any application processing MFER files to limit the impact of potential exploitation. Network-level controls should be applied to restrict access to systems that process biosignal data, especially from untrusted sources. Employing application whitelisting and runtime protections such as stack canaries, ASLR, and DEP can help mitigate exploitation risks. Monitoring for anomalous behavior in biosignal processing applications, including unexpected crashes or unusual network activity, is recommended. Organizations should also engage with The Biosig Project or their software vendors to track patch releases and apply updates promptly once available. For critical environments, consider isolating biosignal processing workloads on segmented networks or dedicated hardware to reduce attack surface.