CVE-2026-40962: FFmpeg before 8.1 has an integer overflow and resultant out-of-bounds write via CENC (Common Encryption) subsa

Q: How do I fix CVE-2026-40962?

ffmpeg: upgrade to 8.1. Exact commands for each OS are on this page.

Q: Is CVE-2026-40962 being exploited?

CVE-2026-40962 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-40962 affect?

CVE-2026-40962 affects ffmpeg. Severity is medium (CVSS 4.9). FFmpeg before 8.1 has an integer overflow and resultant out-of-bounds write via CENC (Common Encryption) subsample data to libavformat/mov.c.

Q: How urgent is CVE-2026-40962?

Priority 18/100. No elevated risk signals yet.

Routine

MEDIUM 4.9UPGRADE

CVE-2026-40962 is a medium-severity flaw (CVSS 4.9) affecting ffmpeg. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

FFmpeg before 8.1 has an integer overflow and resultant out-of-bounds write via CENC (Common Encryption) subsample data to libavformat/mov.c.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	4.9 (Medium)
Attack vector	Local
Attack complexity	High
Privileges needed	None
User interaction	None
EPSS exploit chance	0.1% (top 97%)
CISA exploited list	No
Weakness	CWE-190
Published	2026-04-16
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: ffmpeg

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-16 02:16 UTCPublished CVE record published
2026-06-17 10:45 UTCUpdated Record last modified

ffmpeg ffmpeg UPGRADE

Affected: < 8.1

Fixed in: 8.1

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy ffmpeg || rpm -q ffmpeg || ffmpeg --version

2. UPGRADE to 8.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade ffmpeg

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade ffmpeg

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-40962?

ffmpeg: upgrade to 8.1. Exact commands for each OS are on this page.

Is CVE-2026-40962 being exploited?

CVE-2026-40962 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-40962 affect?

CVE-2026-40962 affects ffmpeg. Severity is medium (CVSS 4.9). FFmpeg before 8.1 has an integer overflow and resultant out-of-bounds write via CENC (Common Encryption) subsample data to libavformat/mov.c.

How urgent is CVE-2026-40962?

Priority 18/100. No elevated risk signals yet.

Software pages

FFmpeg vulnerabilities

Related CVEs

CVE-2026-64831 HIGH 8.8 UPGRADE FFmpeg versions 8.0 through 8.1.2 contains a stack buffer overflow vulnerability in the Vulkan HEVC hardware d
CVE-2026-64834 HIGH 7.5 UPGRADE FFmpeg versions 0.6.3 through 8.1.2 contain an infinite loop vulnerability in the RTP/ASF demuxer within libav
CVE-2026-64830 HIGH 8.8 UPGRADE FFmpeg versions 2.1 through 8.1.2 contains a heap buffer overflow vulnerability in the VobSub subtitle demuxer
CVE-2026-64835 HIGH 8.8 UPGRADE FFmpeg versions 4.4 through 8.1.2 contain an out-of-bounds memory access vulnerability in the ADX audio decode
CVE-2026-64832 HIGH 8.8 UPGRADE FFmpeg versions 4.4 through 8.1.2 contain a double-free vulnerability in the NVIDIA NVDEC hardware decoder wit

References

← Back to latest CVEs