CVE-2026-120243

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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24858
https://github.com/FFmpeg/FFmpeg
https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/g2meet.c#L1040-L1042
https://github.com/FFmpeg/FFmpeg/commit/edad2d0dafcf44fa315eab716fd0183ce808053b
https://www.vulncheck.com/advisories/ffmpeg-2.0-through-9.0.2-information-disclosure-via-g2m-kempf-palette

Configurations

No configuration.

History

01 Nov 2026, 01:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-11-01 01:17

Updated : 2026-11-02 19:34

NVD link : CVE-2026-120243

Mitre link : CVE-2026-120243

CVE.ORG link : CVE-2026-120243

JSON object : View

Products Affected

No product.

CWE

CWE-457

Use of Uninitialized Variable

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