CVE-2021-29976

Mozilla developers reported memory safety bugs present in code shared between Firefox and Thunderbird. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Thunderbird < 78.12, Firefox ESR < 78.12, and Firefox < 90.

• CWE-787

• https://bugzilla.mozilla.org/buglist.cgi?bug_id=1700895%2C1703334%2C1706910%2C1711576%2C1714391Vendor 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/mfsa2021-28/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-29/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-30/Vendor Advisory
• https://bugzilla.mozilla.org/buglist.cgi?bug_id=1700895%2C1703334%2C1706910%2C1711576%2C1714391Vendor 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/mfsa2021-28/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-29/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-30/Vendor Advisory

Published

Aug 5, 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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