CVE-2025-54483 is a critical stack-based buffer overflow vulnerability identified in The Biosig Project's libbiosig library, specifically affecting versions 3.9.0 and the current master branch (commit 35a819fa). The vulnerability resides in the MFER (Multi-File EEG Recording) parsing functionality, which processes neurophysiological data files. The flaw occurs in the biosig.c source file at line 8759, where the code handles the MFER tag 5 (number of channels). The vulnerable code inadequately validates the length of the input data, allowing a specially crafted MFER file with an excessive length field to overflow a stack buffer. This overflow can lead to arbitrary code execution without requiring any user interaction or privileges, as the CVSS vector indicates (AV:N/AC:L/PR:N/UI:N). The vulnerability impacts confidentiality, integrity, and availability, as an attacker can execute arbitrary code remotely by supplying a malicious MFER file to an application using libbiosig for EEG data processing. Given the high CVSS score of 9.8, the exploitability is straightforward, and the impact severe. No known public exploits have been reported yet, but the vulnerability's nature and severity suggest it is a significant risk to any system processing MFER files with libbiosig. The Biosig Project is widely used in biomedical signal processing applications, research environments, and clinical neurophysiology tools, making this vulnerability particularly relevant to those sectors.

For European organizations, the impact of CVE-2025-54483 is substantial, especially for institutions involved in biomedical research, healthcare, and neurophysiological diagnostics that rely on libbiosig for processing EEG and related biosignal data. Successful exploitation could allow attackers to execute arbitrary code on critical systems, potentially leading to data breaches involving sensitive patient information, disruption of clinical services, and compromise of research integrity. The vulnerability threatens confidentiality by exposing sensitive medical data, integrity by allowing manipulation of diagnostic data or research results, and availability by potentially causing system crashes or denial of service. Given the criticality of healthcare infrastructure in Europe and stringent data protection regulations such as GDPR, exploitation could result in regulatory penalties, reputational damage, and operational disruptions. Furthermore, the vulnerability could be leveraged in targeted attacks against research institutions or healthcare providers, especially in countries with advanced biomedical sectors.

To mitigate CVE-2025-54483, European organizations should immediately audit their use of libbiosig, particularly versions 3.9.0 and the affected master branch. Since no official patch links are currently available, organizations should consider the following specific actions: 1) Temporarily disable or restrict processing of MFER files from untrusted or external sources until a patched version is released. 2) Implement strict input validation and sandboxing around any application components that parse MFER files to contain potential exploitation. 3) Monitor network and application logs for unusual activity related to MFER file handling. 4) Engage with the Biosig Project community or maintainers to obtain or contribute to a security patch addressing the buffer overflow. 5) For developers using libbiosig, review and harden the parsing code by adding bounds checking on input lengths, especially for tag 5 processing, and conduct thorough fuzz testing to identify similar vulnerabilities. 6) Employ endpoint protection solutions capable of detecting anomalous behavior indicative of exploitation attempts. 7) Prepare incident response plans specific to potential exploitation scenarios involving biosignal processing systems.