CVE-2026-125244: Memory Corruption (CVSS 7.8)

Description

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains an out-of-bounds write vulnerability in the VVC decoder's sh_entry_points() function in libavcodec/vvc/ps.c. Attackers can supply a crafted VVC (H.266) bitstream whose SPS/PPS tile and WPP layout produces excess entry points, overflowing entry_point_start_ctu and corrupting decoder memory.

Is your site exposed to CVE-2026-125244?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.8

HIGH

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

EPSS — Exploit Prediction

0.0013

Probability of exploitation

0.02%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-787 Out-of-bounds Write

References

Other References

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24537 https://github.com/FFmpeg/FFmpeg https://github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavcodec/vvc/ps.c#L1453 https://github.com/FFmpeg/FFmpeg/commit/a809a784ec9ff9910161c6c9554a041941d6ccce https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-vvc-decoder-out-of-bounds-write-via-sh-entry-points

Frequently Asked Questions

What is CVE-2026-125244? +

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains an out-of-bounds write vulnerability in the VVC decoder's sh_entry_points() function in libavcodec/vvc/ps.c. Attackers can supply a crafted VVC (H.266) bitstream whose SPS/PPS tile and WPP layout produces excess entry points, overflowing entry_point_start_ctu and corrupting decoder memory. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2026-125244? +

CVE-2026-125244 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0013, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-125244? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-8358

LibreOffice Calc can import tracked changes from a spreadsheet document. A heap buffer overflow existed when a document reused the …

CVE-2026-8356

LibreOffice can import presentations in the legacy binary PPT format. A stack buffer overflow existed when importing a colour-replacement record. …

CVE-2026-6040

A heap use-after-free existed when importing the blank-width characters of an ODF number format. A position value read from the …

CVE-2026-6039

LibreOffice can import drawings in the DXF format used by CAD software. A heap buffer overflow existed when importing a …

CVE-2026-3298

The method "sock_recvfrom_into()" of "asyncio.ProacterEventLoop" (Windows only) was missing a boundary check for the data buffer when using nbytes parameter. …

CVE-2026-40489

editorconfig-core-c is an EditorConfig core library for use by plugins supporting EditorConfig parsing. Versions up to and including 0.12.10 have …