LibbiosigApplication · Libbiosig Project

CVE-2025-66048

CRITICAL · 9.8 CVSS v3.1 Published 2025-12-11
Fix available
A fix is available. Upgrade to 3.9.2 or later.
See remediation →
100/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Several stack-based buffer overflow vulnerabilities exists in the MFER parsing functionality of The Biosig Project libbiosig 3.9.1. A specially crafted MFER file can lead to arbitrary code execution. An attacker can provide a malicious file to trigger these vulnerabilities.When Tag is 133

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Stack-based buffer overflow vulnerabilities exist in the MFER file parsing code of libbiosig 3.9.1. When processing MFER files with specific Tag values (noted as Tag 133), the parser fails to perform proper bounds checking before writing data to a stack-allocated buffer, allowing an attacker-controlled file to overflow the buffer and achieve arbitrary code execution.

MitigationUpgrade libbiosig to the latest version containing the security patch, or implement input validation and bounds checking in the MFER parsing routines to ensure all file read operations respect buffer boundaries before processing Tag 133 and similar constructs.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
LibbiosigApplication
Affected:< 3.9.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed libbiosig version
    Run 'pkg-config --modversion libbiosig' or check the library file version metadata using 'strings' or 'file' on the compiled library binary, or review build/package manifests if installed via a package manager
    Affected if The reported version is lower than 3.9.2 (e.g., 3.9.1 or earlier)
  2. Confirm MFER file parsing capability is present
    Check if the libbiosig library binary contains MFER-related symbols or functions by running 'nm -g <library> | grep -i mfer' or 'objdump -T <library> | grep -i mfer'
    Affected if MFER parsing functions exist in the installed library binary
  3. Locate applications or tools that use libbiosig
    Search for executables or scripts that link against libbiosig and process MFER files, using 'ldd <executable>' or checking application documentation for MFER support
    Affected if Applications linked against the vulnerable libbiosig version are in use for processing MFER files
  4. Review MFER file processing workflows
    Audit any file import or data ingestion pipelines that handle .mfer files, noting whether libbiosig is invoked to parse them
    Affected if MFER files are being processed by the vulnerable library version

A user is affected if their installed libbiosig version is below 3.9.2 and they process MFER files using the library, particularly files with Tag 133 constructs.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 3.9.2 or later
Fixed in 3.9.2
Interim mitigation

Upgrade libbiosig to the latest version containing the security patch, or implement input validation and bounds checking in the MFER parsing routines to ensure all file read operations respect buffer boundaries before processing Tag 133 and similar constructs.

Recommended fix Moderate confidence

libbiosig 3.9.2

  1. Obtain libbiosig version 3.9.2 or later from the official Biosig Project repository or distribution channel
  2. Replace the vulnerable libbiosig installation with the version 3.9.2 or later
  3. Recompile any applications that link against libbiosig to ensure they use the updated library
  4. Verify the new version is correctly installed by checking the library version
  5. Re-test the MFER parsing functionality with legitimate files to confirm proper operation

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Libbiosig Scoped from the published advisory
  • Consultation2.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
16.0 hours of engineering $2,800
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,480.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-66048 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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