CVE-2021-38496

HighCVSS 8.8/10Last modified Jun 17, 2026

Description

During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.

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-416

Affected software

Vendor	Product	Versions
Mozilla	Thunderbird	>= unspecified, < 78.15; >= unspecified, < 91.2
Mozilla	Firefox ESR	>= unspecified, < 91.2; >= unspecified, < 78.15
Mozilla	Firefox	>= unspecified, < 93

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1725335Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.htmlMailing List, Third Party Advisory
https://www.debian.org/security/2022/dsa-5034Issue Tracking, Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2021-43/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-44/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-45/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-46/Broken Link
https://www.mozilla.org/security/advisories/mfsa2021-47/Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1725335Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.htmlMailing List, Third Party Advisory
https://www.debian.org/security/2022/dsa-5034Issue Tracking, Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2021-43/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-44/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-45/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-46/Broken Link
https://www.mozilla.org/security/advisories/mfsa2021-47/Vendor Advisory

Timeline

Published: Nov 3, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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