dbcve.org
FfmpegApplication

CVE-2021-28429

MEDIUM · 5.5 CVSS v3.1 Published 2023-08-11
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
57/100
Remediation priority · Elevated
Zero-click Patch available

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
Integer overflow vulnerability in av_timecode_make_string in libavutil/timecode.c in FFmpeg version 4.3.2, allows local attackers to cause a denial of service (DoS) via crafted .mov file.

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
How this class of weakness works · CWE-190

An arithmetic operation produces a value too large for its type and wraps around to an unexpected — often tiny or negative — number. That miscalculated value then drives a memory allocation or a bounds check, opening the door to corruption. The fix is checked arithmetic and validating sizes before they're used.

General guidance for the integer overflow class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

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
FfmpegApplication
Affected:= 4.3.2

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
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

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
Patch available Apply the vendor patch
Vendor patch git.ffmpeg.org →
Recommended fix High confidence

FFmpeg 4.4.1 or later stable release

  1. 1. Check current FFmpeg version by running: ffmpeg -version
  2. 2. Obtain FFmpeg version 4.4.1 or later which contains the fix for this integer overflow vulnerability
  3. 3. If using a package manager (apt, yum, brew, etc.), update: apt-get update && apt-get install ffmpeg (or respective command for your package manager)
  4. 4. If building from source, clone FFmpeg and checkout the fixed version tag (e.g., n4.4.1) or apply the patch from commit c94875471e3ba3dc396c6919ff3ec9b14539cd71
  5. 5. Verify the fix by running: ffmpeg -version to confirm the updated version is installed
  6. 6. Test with the crafted .mov file to confirm the overflow is now handled properly and does not cause a denial of service
Caveat Minimal - this is a bug fix for an integer overflow in timecode handling; no API/ABI changes expected

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

We can apply and verify the patch for your build — typical engagement from $2,850. Get the patch applied

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-28429 — 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-2021-28429 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