dbcve.org
NULL Pointer DereferenceWeakness · CWE-476

CVE-2025-25473

MEDIUM · 5.3 CVSS v3.1 Published 2025-02-18
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
62/100
Remediation priority · Elevated
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
FFmpeg git master before commit c08d30 was discovered to contain a memory leak in the avformat_free_context function in libavutil/mem.c.

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

A memory leak exists in FFmpeg's avformat_free_context function in libavutil/mem.c in versions prior to commit c08d30. The function fails to properly release allocated memory, which can cause resource exhaustion during extended media processing operations.

MitigationUpdate FFmpeg to a version built after commit c08d30, or backport the specific patch that fixes the memory leak in avformat_free_context.

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

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
None
Integrity
Low
Availability
None

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

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. Verify FFmpeg is installed
    Run 'ffmpeg -version' or 'which ffmpeg' to confirm FFmpeg is present on the system
    Affected if FFmpeg is not installed, the system is not affected by this vulnerability
  2. Determine installed FFmpeg version
    Run 'ffmpeg -version' and note the version string (e.g., 6.1, 7.0, etc.)
    Affected if Unable to determine version - the check cannot be completed
  3. Check if version includes the fix
    Review FFmpeg release notes or git log for commit c08d30 inclusion; compare your version against the release that contains the fix
    Affected if The installed version was released before the fix for commit c08d30 was integrated
  4. Identify if avformat operations are used
    Review application code or runtime logs for usage of avformat functions (avformat_open_input, avformat_free_context, or similar avformat APIs) that process media files
    Affected if No avformat-based media processing occurs, the memory leak path is not triggered

The environment is affected if FFmpeg is installed with a version that predates the fix for commit c08d30 and the system performs avformat-based media processing that invokes avformat_free_context.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update FFmpeg to a version built after commit c08d30, or backport the specific patch that fixes the memory leak in avformat_free_context.

Have this fixed Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-25473 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2025-25473 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data