CVE-2026-70632: ffmpeg Out-of-bounds Write
Vulnerability summary
CVE-2026-70632 is a high (CVSS 8.5) Out-of-bounds Write vulnerability in ffmpeg. EPSS estimates a 0.20% chance of exploitation in the next 30 days, higher than 9.5% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 10 · Related 9Timeline
- 06-08-2026PublishedVulnerability first disclosed.
- 14-08-2026Last modifiedVulnerability information updated.
Description
FFmpeg versions from 4.4 up to, but not including, 9.0 contain an out-of-bounds heap write vulnerability in the native GoPro CineForm HD (CFHD) decoder that allows remote attackers to corrupt heap memory by supplying a crafted AVI file during stream probing. The cfhd_decode() function fails to enforce the non-Bayer logical output-width invariant in the transform-type-2 reconstruction path, causing horiz_filter_clip() to write oversized 16-bit sample rows far beyond the allocated output frame buffer, which can be escalated to arbitrary code execution via overwrite of a live cleanup callback pointer.
CVSS metrics
9 scores · 6 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated8.5HighCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- OSV · DebianEcosystem advisory · calculated8.5HighCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · WolfiEcosystem advisory · calculated8.5HighCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- OSV · ChainguardEcosystem advisory · calculated8.5HighCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- NVDNIST8.5HighCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.20%
Chance of exploitation in the next 30 days
Percentile
10%
Versus all other CVEs
30-day change
0.00 pp
From 0.20% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Chainguard14 products
- eco-python-ffmpeg-6-minimalAll versions (No fix recorded)
- eco-python-ffmpeg-6-minimal-devAll versions (No fix recorded)
- eco-python-ffmpeg-6-minimal-staticAll versions (No fix recorded)
- eco-python-ffmpeg-7-minimalAll versions (No fix recorded)
- eco-python-ffmpeg-7-minimal-devAll versions (No fix recorded)
Wolfi4 products
- ffmpeg-7All versions (No fix recorded)
- ffmpeg-7.1All versions (No fix recorded)
- ffmpeg-8.0All versions (No fix recorded)
- ffmpeg-8.1All versions (No fix recorded)
Ubuntu2 products
- ffmpeg< 7:4.4.2-0ubuntu0.22.04.1+esm14 | < 7:6.1.1-3ubuntu5+esm12 | All versions (No fix recorded) | < 7:8.0.1-3ubuntu2+esm3
- libavAll versions (No fix recorded)
Debian1 product
- ffmpegAll versions (No fix recorded) | < 7:9.0.2-1
Ffmpeg1 product
- ffmpeg≥ 4.4, < 9.0 | ≥ 4.4, < 9
5 vendors · 22 products
References
13 links- www.vulncheck.com/advisories/ffmpeg-heap-out-of-bounds-write-in-cfhd-decoder-via-avi-demuxingThird Party AdvisoryAdvisoryPatch
