CVE-2021-29980

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.

• CWE-909

• https://bugzilla.mozilla.org/show_bug.cgi?id=1722204Exploit, Issue Tracking, Vendor Advisory
• https://security.gentoo.org/glsa/202202-03Third Party Advisory
• https://security.gentoo.org/glsa/202208-14Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-33/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-34/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-35/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-36/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1722204Exploit, Issue Tracking, Vendor Advisory
• https://security.gentoo.org/glsa/202202-03Third Party Advisory
• https://security.gentoo.org/glsa/202208-14Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-33/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-34/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-35/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-36/Vendor Advisory

Published

Aug 17, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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• CVE-2021-29974When network partitioning was enabled, e.g. as a result of E…4.3
• CVE-2021-29975Through a series of DOM manipulations, a message, over which…6.5
• CVE-2021-29976Mozilla developers reported memory safety bugs present in co…8.8
• CVE-2021-29977Mozilla developers reported memory safety bugs present in Fi…8.8
• CVE-2021-29978Multiple low security issues were discovered and fixed in a …9.8
• CVE-2021-29979Hubs Cloud allows users to download shared content, specific…6.1
• CVE-2021-29981An issue present in lowering/register allocation could have …8.8
• CVE-2021-29982Due to incorrect JIT optimization, we incorrectly interprete…6.5
• CVE-2021-29983Firefox for Android could get stuck in fullscreen mode and n…6.5
• CVE-2021-29984Instruction reordering resulted in a sequence of instruction…8.8
• CVE-2021-29985A use-after-free vulnerability in media channels could have …8.8
• CVE-2021-29986A suspected race condition when calling getaddrinfo led to m…8.1