Overview
In the realm of cybersecurity, a newly discovered stack-based buffer overflow vulnerability, CVE-2025-54487, threatens the security of systems utilizing The Biosig Project libbiosig 3.9.0 and Master Branch (35a819fa). This vulnerability is particularly dangerous due to its potential to allow arbitrary code execution, thus providing an attacker with an avenue to compromise a system or leak sensitive data. Given its severity and potential impact, it is vital for organizations and individuals alike to understand the nature of this vulnerability and take proactive steps to mitigate its risks.
Vulnerability Summary
CVE ID: CVE-2025-54487
Severity: Critical (9.8)
Attack Vector: Remote
Privileges Required: None
User Interaction: No
Impact: Potential system compromise or 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 originates from the MFER parsing functionality in the Biosig Project libbiosig 3.9.0 and Master Branch. When parsing a specially crafted MFER file, an attacker could trigger arbitrary code execution. This is caused by a stack-based buffer overflow vulnerability present on line 8842 of biosig.c on the current master branch (35a819fa), when the Tag is 12.
Values of `len` greater than 130 or smaller than 2 can trigger this overflow. The latter case can cause an integer underflow when calculating `len-2` in the given code path, leading to buffer overflow and a potential for malicious code execution.
Conceptual Example Code
The following pseudocode illustrates a potential exploit:
#include <stdio.h>
// Assume the following MFER file structure
struct MFER {
int tag;
int len;
char buf[128];
};
// An attacker could craft an MFER file as follows:
struct MFER malicious_file;
malicious_file.tag = 12;
malicious_file.len = 131; // or malicious_file.len = 1;
// The buffer is filled with malicious payload
for (int i = 0; i < malicious_file.len; i++) {
malicious_file.buf[i] = 'A'; // This could be replaced with malicious code
}In this conceptual example, an attacker crafts an MFER file with a `tag` of 12 and a `len` value of 131 or 1. This `len` value triggers the buffer overflow in the Biosig Project libbiosig 3.9.0, allowing the attacker’s malicious code to be executed.
Mitigation and Recommendations
The best mitigation for this vulnerability is to apply the patch provided by the vendor. If the patch cannot be applied immediately, using Web Application Firewalls (WAFs) or Intrusion Detection Systems (IDS) can offer temporary mitigation. It is also advisable to restrict the processing of untrusted MFER files until the patch is applied.
