CVE-2023-6856

HighCVSS 8.8/10Last modified Jun 17, 2026

Description

The WebGL `DrawElementsInstanced` method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution and sandbox escape. This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.

Metrics

CVSS 3.1 8.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-787

Affected software

No affected versions have been published.

Timeline

Published: Dec 19, 2023
Last modified: Jun 17, 2026
NVD status: Modified

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