Overview
The Biosig Project libbiosig, a popular biosignal processing library, has been discovered to contain a severe heap-based buffer overflow vulnerability. This vulnerability, allocated the identifier CVE-2025-53853, affects version 3.9.0 and the Master Branch (35a819fa) of libbiosig. The exploitation of this vulnerability could lead to arbitrary code execution, potentially compromising the entire system or leading to data leakage. This vulnerability is of significant importance due to its high severity and the widespread use of the Biosig Project’s libbiosig in the healthcare industry.
Vulnerability Summary
CVE ID: CVE-2025-53853
Severity: Critical (CVSS 9.8)
Attack Vector: File
Privileges Required: None
User Interaction: Required
Impact: System compromise and potential data leakage
Affected Products
Share secrets securely
Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.
Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.
- • Encrypted identity
- • Private Spaces for organizations and teams
- • End-to-end encrypted chat, calls, files, and notes
- • Sensitive AI work and protected collaboration
- • Built for information that cannot leak
Our mission is to secure human work alongside AI.
Product | Affected Versions
Biosig Project libbiosig | 3.9.0, Master Branch (35a819fa)
How the Exploit Works
The vulnerability resides in the ISHNE parsing functionality of libbiosig. An attacker can exploit this vulnerability by crafting a malicious ISHNE ECG annotations file. When this file is processed by the vulnerable software, it triggers a buffer overflow. This overflow occurs because the software fails to properly validate the size of the input data before copying it to a fixed-size buffer. This can lead to overwriting of adjacent memory spaces, allowing the attacker to execute arbitrary code.
Conceptual Example Code
Given that the vulnerability occurs during the parsing of an ISHNE ECG annotations file, the exploit would likely involve the creation of such a file with specially designed data to trigger the overflow. A conceptual example might look like this:
#include <stdio.h>
#include <string.h>
int main(void) {
char buffer[512];
FILE *fp;
memset(buffer, 'A', sizeof(buffer)-1); // Fill the buffer with 'A's
buffer[sizeof(buffer)-1] = '\0'; // Null terminate the string
fp = fopen("malicious.ishne", "w");
fwrite(buffer, sizeof(char), sizeof(buffer), fp); // Write the buffer to the file
fclose(fp);
return 0;
}This conceptual example creates a malicious ISHNE ECG annotations file that contains a string of ‘A’s longer than the buffer size. When the file is processed by the vulnerable software, it would trigger the buffer overflow.
Recommended Mitigation
Users are advised to apply the vendor patch immediately if available. If the patch is not available or if immediate patching is not feasible, users should consider using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as a temporary mitigation measure to detect and block attempts to exploit this vulnerability.