Cyber Posture

CVE-2025-54493

CriticalPublic PoC

Published: 25 August 2025

Published
25 August 2025
Modified
03 November 2025
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0033 55.9th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-54493 is a critical-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Libbiosig Project Libbiosig. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 44.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Requires validation of input lengths and structures in MFER files before reading into fixed-size buffers, directly preventing the buffer overflow triggered by tag 131 with incorrect length.

prevent

Implements memory protections such as stack canaries, ASLR, and DEP to block exploitation of stack-based buffer overflows even if input validation fails.

prevent

Mandates timely remediation of identified flaws like the buffer overflow in libbiosig's MFER parsing, preventing exploitation through patching.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
Why these techniques?

Stack-based buffer overflow in file parser enables remote arbitrary code execution via crafted input with no auth/UI required.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD 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…

more

trigger this vulnerability.This vulnerability manifests on line 9184 of biosig.c on the current master branch (35a819fa), when the Tag is 131: else if (tag==131) //0x83 { // Patient Age if (len!=7) fprintf(stderr,"Warning MFER tag131 incorrect length %i!=7\n",len); curPos += ifread(buf,1,len,hdr);

Deeper analysisAI

A stack-based buffer overflow vulnerability, tracked as CVE-2025-54493 and associated with CWE-121, affects the MFER parsing functionality in The Biosig Project's libbiosig version 3.9.0 and the master branch at commit 35a819fa. The issue occurs in biosig.c at line 9184 during handling of tag 131 (0x83), where a specially crafted MFER file can cause the overflow. This leads to arbitrary code execution when the file is parsed, as the code reads data into a fixed-size buffer without sufficient bounds checking, even issuing only a warning for incorrect lengths rather than preventing the read.

The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating it is exploitable remotely with low complexity, requiring no privileges or user interaction. Any attacker capable of supplying a malicious MFER file to an application or system that uses libbiosig for parsing can trigger the overflow, potentially achieving arbitrary code execution with the privileges of the parsing process.

Advisories are available from Talos Intelligence at https://talosintelligence.com/vulnerability_reports/TALOS-2025-2234 and https://www.talosintelligence.com/vulnerability_reports/TALOS-2025-2234.

Details

CWE(s)

Affected Products

libbiosig project
libbiosig
≤ 3.9.1

CVEs Like This One

CVE-2025-54485Same product: Libbiosig Project Libbiosig
CVE-2025-54482Same product: Libbiosig Project Libbiosig
CVE-2025-54487Same product: Libbiosig Project Libbiosig
CVE-2025-54484Same product: Libbiosig Project Libbiosig
CVE-2025-54486Same product: Libbiosig Project Libbiosig
CVE-2025-54491Same product: Libbiosig Project Libbiosig
CVE-2025-54492Same product: Libbiosig Project Libbiosig
CVE-2025-54480Same product: Libbiosig Project Libbiosig
CVE-2025-54489Same product: Libbiosig Project Libbiosig
CVE-2025-54490Same product: Libbiosig Project Libbiosig

References