Vulnerability · Published Aug 6, 2026 · Assigned by VulnCheck

CVE-2026-70628FFmpeg 0.5 < 9.0 DVB Subtitle Parser Heap Buffer Overflow via WTV File

High 7.8

In plain English

A high-severity integer overflow in FFmpeg from FFmpeg. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.8High

Exploit odds (30 days)0.1%top 96.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

FFmpeg versions from 0.5 up to, but not including, 9.0 contain a signed integer overflow vulnerability in the DVB subtitle parser in libavcodec/dvbsub_parser.c that allows attackers to trigger a heap buffer overflow by supplying a crafted WTV file. The overflow causes the bounds-check guard expression to wrap to INT_MIN, bypassing the PARSE_BUF_SIZE comparison and invoking memcpy() with attacker-controlled data into a heap buffer, resulting in an out-of-bounds heap write and potential memory corruption or code execution.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	ffmpeg	no fix listed	DEBIAN-CVE-2026-70628
Debian:13	ffmpeg	no fix listed	DEBIAN-CVE-2026-70628
Debian:14	ffmpeg	7:9.0.2-1	DEBIAN-CVE-2026-70628
Ubuntu:26.10	ffmpeg	no fix listed	UBUNTU-CVE-2026-70628

Affected products (as reported)

Vendor	Product	Versions
FFmpeg	FFmpeg	0.5 – before 9.0

Weakness: CWE-190, CWE-787 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

Pull Request issue-tracking
Introducing Commit related
Patch Commit patch
FFmpeg 9.0 Backport Commit patch
https://www.vulncheck.com/advisories/ffmpeg-dvb-subtitle-parser-heap-buffer-overflow-via-wtv-file third-party-advisory