CVE-2025-54480Public exploitNetwork attack vector

Code execution via unchecked MFER Tag 0 length

Published Aug 25, 2025 · Updated Nov 3, 2025

Stack-based buffer overflow in libbiosig 3.9.0 and Master Branch (35a819fa) allows attackers to execute arbitrary code via a crafted MFER file. In sopen_extended, the Tag 0 branch warns when the decoded length is not 1 but still passes that untrusted length to ifread, which writes into a 128-byte stack buffer without a bounds check. Reachability requires the crafted file to enter a consuming application's MFER read path; successful exploitation runs code in that application's context.

CVSS severity9.8
Critical
EPSS probability0.71%
Next 30 days · Sep 17, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stack-based buffer overflow in libbiosig 3.9.0 and Master Branch (35a819fa) allows attackers to execute arbitrary code via a crafted MFER file. In sopen_extended, the Tag 0 branch warns when the decoded length is not 1 but still passes that untrusted length to ifread, which writes into a 128-byte stack buffer without a bounds check. Reachability requires the crafted file to enter a consuming application's MFER read path; successful exploitation runs code in that application's context.

The record

CVE
CVE-2025-54480
Published
Aug 25, 2025
Updated
Nov 3, 2025
Vendor
The BioSig Project
Product
libbiosig
Classifications
CWE-121, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 25, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.9.0
  2. Affected versionversion=Master Branch (35a819fa)

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The BioSig Project · libbiosigversion=3.9.0; version=Master Branch (35a819fa)

Published CVSS scores

9.8Cisco TalosCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 11, 2026Sep 17, 2026
Latest reporting daySep 17, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo