FFmpeg before 8.1.3 and 9.x before 9.0.2 VVC Decoder Out-of-Bounds Write via sh_entry_points
Affects FFmpeg from 7.0 before 8.1.3 and from 9.0 before 9.0.2 when decoding crafted VVC (H.266) bitstreams with a particular tile and WPP layout. Fixed in 8.1.3 and 9.0.2.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 8.1.3, 9.0.2
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Attacker supplies a crafted VVC (H.266) bitstream whose SPS/PPS tile and WPP layout produces excess entry points Affected FFmpeg versions are 7.0 up to 8.1.3 and 9.0 up to 9.0.2
- Last modified
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 14/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
FFmpeg versions before 8.1.3 and 9.x before 9.0.2 contain a flaw in the VVC decoder that lets an attacker who has crafted a VVC (H.266) video file overwrite memory outside its intended bounds, which can corrupt the decoder's memory. The attack is local and requires a user to open the malicious file.
Read the original 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.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure5/25Specific setups only
- Reach?/20Unknown. No tracked technology or package matched
- Severity8.5/10CVSS 8.5
- No patch0/5No signal
What would change the score
- Would score about 64 if added to CISA KEV
- Would score about 59 if CISA's SSVC rates exploitation active
- Would score about 24 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Attacker supplies a crafted VVC (H.266) bitstream whose SPS/PPS tile and WPP layout produces excess entry points Affected FFmpeg versions are 7.0 up to 8.1.3 and 9.0 up to 9.0.2Upgrade to a fixed version: 8.1.3, 9.0.2.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- FFmpeg FFmpeg
From 7.0 · fixed in 8.1.3; From 9.0 · fixed in 9.0.2
Evidence 5
- Patch
- Report
- Repository
- Repository
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-125244
Is CVE-2026-125244 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
A crafted VVC (H.266) bitstream whose SPS/PPS tile and WPP layout produces excess entry points makes the decoder write past the end of entry_point_start_ctu. The overflow corrupts decoder memory.Source: vulncheck.com
Which versions are affected by CVE-2026-125244?
FFmpeg: from 7.0 before 8.1.3; from 9.0 before 9.0.2.Source: cve.now feed data
Am I affected, and how do I check?
FFmpeg 7.0 before 8.1.3 and 9.0 before 9.0.2 are in the affected range. Check the installed version with ffmpeg -version, and note that the bug needs VVC decoding with the tile and WPP layout described above.Source: vulncheck.com
How do I fix CVE-2026-125244?
Upgrade to FFmpeg 8.1.3 or 9.0.2, or to a later release. The facts list no workaround.Source: vulncheck.com