CVE-2025-54489

9.8 CRITICAL
Published: August 25, 2025 Modified: November 03, 2025

Description

A stack-based buffer overflow vulnerability exists in the MFER parsing functionality of The Biosig Project libbiosig 3.9.0 and Master Branch (35a819fa). A specially crafted MFER file can lead to arbitrary code execution. An attacker can provide a malicious file to trigger this vulnerability.This vulnerability manifests on line 8970 of biosig.c on the current master branch (35a819fa), when the Tag is 63: else if (tag==63) { uint8_t tag2=255, len2=255; count = 0; while ((count<len) && !(FlagInfiniteLength && len2==0 && tag2==0)){ curPos += ifread(&tag2,1,1,hdr); curPos += ifread(&len2,1,1,hdr); if (VERBOSE_LEVEL==9) fprintf(stdout,"MFER: tag=%3i chan=%2i len=%-4i tag2=%3i len2=%3i curPos=%i %li count=%4i\n",tag,chan,len,tag2,len2,curPos,iftell(hdr),(int)count); if (FlagInfiniteLength && len2==0 && tag2==0) break; count += (2+len2); curPos += ifread(&buf,1,len2,hdr); Here, the number of bytes read is not the Data Length decoded from the current frame in the file (`len`) but rather is a new length contained in a single octet read from the same input file (`len2`). Despite this, a stack-based buffer overflow condition can still occur, as the destination buffer is still `buf`, which has a size of only 128 bytes, while `len2` can be as large as 255.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://talosintelligence.com/vulnerability_reports/TALOS-2025-2234
Source: talos-cna@cisco.com
Exploit Third Party Advisory

2 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.8 / 10.0
EPSS (Exploit Probability)
0.2%
48th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

libbiosig_project