CVE-2026-70629: ffmpeg Use of Uninitialized Resource
Vulnerability summary
CVE-2026-70629 is a medium (CVSS 6.8) Use of Uninitialized Resource vulnerability in ffmpeg. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 6.5% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 9 · Related 8Timeline
- 06-08-2026PublishedVulnerability first disclosed.
- 14-08-2026Last modifiedVulnerability information updated.
Description
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder (libavcodec/rscc.c) that allows attackers to disclose heap memory contents by supplying a crafted video file with a compressed tile that decompresses fewer bytes than the declared tile geometry requires. When rscc_decode_frame() calls av_image_copy_plane() without validating the decompressed byte count against the tile dimensions, the unwritten suffix of the persistent intermediate buffer ctx->inflated_buf is copied into the decoded frame, potentially exposing data from prior heap allocations or previous decoded frames in persistent decoding services.
CVSS metrics
9 scores · 6 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated6.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- OSV · DebianEcosystem advisory · calculated6.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/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 · calculated6.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- OSV · ChainguardEcosystem advisory · calculated6.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- NVDNIST6.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/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 · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- NVDNIST5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS trend
Probability
0.18%
Chance of exploitation in the next 30 days
Percentile
7%
Versus all other CVEs
30-day change
+0.05 pp
From 0.13% 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
- ffmpegAll versions (No fix recorded) | < 7:4.2.7-0ubuntu0.1+esm17 | < 7:4.4.2-0ubuntu0.22.04.1+esm16
- libavAll versions (No fix recorded)
Debian1 product
- ffmpegAll versions (No fix recorded) | < 7:9.0.2-1
Ffmpeg1 product
- ffmpeg≥ 3.0, < 9.0 | ≥ 3.0, < 9
5 vendors · 22 products
References
12 links- www.vulncheck.com/advisories/ffmpeg-uninitialized-heap-memory-read-in-rscc-decoderThird Party AdvisoryAdvisoryPatch
