CVE-2025-54462: Heap-based Buffer Overflow Vulnerability in Biosig Project

Overview

In this comprehensive review, we delve into CVE-2025-54462, a severe cybersecurity vulnerability that has been identified in the Nex parsing functionality of The Biosig Project libbiosig 3.9.0 and Master Branch. This vulnerability, classified as a heap-based buffer overflow, is particularly significant due to its potential to allow an attacker to execute arbitrary code, leading to a potential system compromise or data leakage. As such, this vulnerability presents a substantial threat to any organizations or individuals using the affected versions of the Biosig Project.

Vulnerability Summary

CVE ID: CVE-2025-54462
Severity: Critical (CVSS score 9.8)
Attack Vector: Remote
Privileges Required: None
User Interaction: Required
Impact: Successful exploitation could lead to arbitrary code execution, potential system compromise, and data leakage.

Affected Products

Product | Affected Versions

Biosig Project libbiosig | 3.9.0 and Master Branch (35a819fa)

How the Exploit Works

A heap-based buffer overflow vulnerability occurs when a program writes more data to a buffer located on the heap than what’s allocated for it. This overflow can corrupt data, crash the program, or lead to the execution of malicious code. In the case of CVE-2025-54462, a specially crafted .nex file can trigger this vulnerability, allowing an attacker to execute arbitrary code.

Conceptual Example Code

Consider the following hypothetical scenario. An attacker crafts a malicious .nex file designed to overflow the buffer in the affected Biosig Project software. The attacker then sends this file to the target system, either through an email attachment or other delivery methods. Once the target opens this file with the vulnerable software, the overflow is triggered, potentially leading to arbitrary code execution, as demonstrated in the pseudo-code below:

# pseudo-code for the malicious .nex file
buffer = 'A' * 1024  # creates a buffer with size greater than what's allocated
file = open('malicious.nex', 'w')  # opens a new .nex file
file.write(buffer)  # writes the buffer to the .nex file
file.close()  # closes the file

Note: This is a simplified representation of how the exploit might work. The actual exploit would likely involve more complex code and interactions with the Biosig Project software.
This vulnerability highlights the importance of proper input validation and buffer management in software development. As a preventive measure, organizations are encouraged to apply the vendor patch or use WAF/IDS as a temporary mitigation.