Overview
The BIOSIG project’s libbiosig version 3.9.0, a popular software library for biomedical signal processing, contains a critical vulnerability that potentially allows a successful attacker to execute arbitrary code on the affected system. This vulnerability, assigned the identifier CVE-2025-54493, exists in the MFER parsing functionality of the software. It’s of paramount importance due to its severity, the widespread usage of the library, and the potential for system compromise or data leakage.
Vulnerability Summary
CVE ID: CVE-2025-54493
Severity: Critical (9.8 CVSS Score)
Attack Vector: File
Privileges Required: None
User Interaction: Required
Impact: System compromise, potential data leakage
Affected Products
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Product | Affected Versions
The Biosig Project libbiosig | 3.9.0, Master Branch (35a819fa)
How the Exploit Works
The vulnerability stems from a stack-based buffer overflow in the MFER parsing functionality. Specifically, it manifests when a specially crafted MFER file is processed, triggering arbitrary code execution. When the Tag is 131 during processing, as seen on line 9184 of biosig.c on the current master branch, an improper length check can cause the buffer overflow.
Conceptual Example Code
Conceivably, an attacker could create a malicious MFER file with a specific tag of 131, but with a length not equal to 7. The example below outlines the potential structure of such a file:
Tag: 131
Length: 10
Data: [malicious code]In this scenario, the crafted MFER file would exploit the buffer overflow vulnerability when processed, potentially leading to arbitrary code execution.
Impact of the Exploit
A successful exploit of this vulnerability could lead to the compromise of the system running the vulnerable software version. Depending on the permissions of the process, this could allow an attacker to view, modify or delete data, create new accounts with full user rights, and even introduce additional malicious software to further compromise the system.
Recommended Mitigations
Users of the affected software should apply the vendor patch as soon as it becomes available to mitigate this vulnerability. In the meantime, employing a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as temporary mitigation, potentially alerting to or blocking attempts to exploit this vulnerability.
Regular software updates and patch management, alongside a robust cybersecurity framework, can greatly reduce the risk of such vulnerabilities being successfully exploited.