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Fencer Vulns
medium 5.5

CVE-2026-120243 json

FFmpeg 2.0 through 9.0.2 Information Disclosure via G2M Kempf Palette

published 2026-11-01 8 d ago modified 2026-11-06 2 d ago also EUVD-2026-114740

cvss
5.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 2%
public exploits
0
none known

Summary

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.

Patch / fix

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-120243 updated cvss 5.5

ffmpeg: ffmpeg: information disclosure via crafted Go2Meeting stream

  • Red Hat Enterprise Linux AI (RHEL AI) 3 ffmpeg 6.1.6-10.el9ai, rhelai3/bootc-cuda-rhel9, rhelai3/bootc-rocm-rhel9, rhelai3/bootc-aws-cuda-rhel9, rhelai3/bootc-gcp-cuda-rhel9, rhelai3/bootc-azure-cuda-rhel9, +1 more Red Hat OpenShift AI (RHOAI) rhoai/odh-vllm-gaudi-rhel9
    affected: no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 d ago

Exploit prediction

0.12% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 6.8 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
CNA 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CNA 4.0 6.8 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/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

Affected products

  • FFmpeg FFmpeg

Classification

Weakness
  • CWE-457 Use of Uninitialized Variable

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.