CVE-2026-120243

medium

Description

FFmpeg 2.0 through 9.0.2 contains a use of uninitialized variable vulnerability in the Go2Meeting decoder that allows attackers to leak stack memory through out-of-range palette indices. Attackers can craft a G2M3/G2M4 stream with a short Kempf palette so kempf_restore_buf() copies uninitialized stack bytes, including pointers or stack guards, into decoded output.

References

https://www.vulncheck.com/advisories/ffmpeg-2.0-through-9.0.2-information-disclosure-via-g2m-kempf-palette

https://github.com/FFmpeg/FFmpeg/commit/edad2d0dafcf44fa315eab716fd0183ce808053b

https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/g2meet.c#L1040-L1042

https://github.com/FFmpeg/FFmpeg

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-114740

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24858

Details

Source: Mitre, NVD

Published: 2026-11-01

Updated: 2026-11-01

Risk Information

CVSS v2

Base Score: 4.9

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.5

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

Severity: Medium

CVSS v4

Base Score: 6.8

Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.00124