CVE-2021-29980

HIGH

Thunderbird <78.13, Firefox ESR <78.13, Firefox <91 - Memory Corrup...

Title source: llm

Description

Uninitialized memory in a canvas object could have caused an incorrect free() leading to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.

References (7)

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2021-33/

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2021-35/

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2021-34/

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2021-36/

[Exploit, Issue Tracking, Vendor Advisory] https://bugzilla.mozilla.org/show_bug.cgi?id=1722204

[Third Party Advisory] https://security.gentoo.org/glsa/202202-03

[Third Party Advisory] https://security.gentoo.org/glsa/202208-14

Scores

CVSS v3 8.8

EPSS 0.0041

EPSS Percentile 61.4%

Attack Vector NETWORK

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

Details

CWE

CWE-909

Status published

Products (3)

mozilla/firefox < 91.0

mozilla/firefox_esr < 78.13.0

mozilla/thunderbird < 78.13.0

Published Aug 17, 2021

Tracked Since Feb 18, 2026