vulnerability

MFSA2023-55 Thunderbird: Security Vulnerabilities fixed in Thunderbird 115.6 (CVE-2023-6856)

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Severity

CVSS

(AV:N/AC:M/Au:N/C:C/I:C/A:C)

Published

Dec 19, 2023

Added

Dec 20, 2023

Modified

Mar 27, 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.

Solution

mozilla-thunderbird-upgrade-115_6

References

CVE-2023-6856
https://attackerkb.com/topics/CVE-2023-6856
CWE-787
EUVD-EUVD-2023-59060
http://www.mozilla.org/security/announce/2023/mfsa2023-55.html
https://euvd.enisa.europa.eu/vulnerability/EUVD-2023-59060

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