vulnerability

MFSA2021-36 Thunderbird: Security Vulnerabilities fixed in Thunderbird 91 (CVE-2021-29981)

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Severity

CVSS

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

Published

Aug 11, 2021

Added

Aug 12, 2021

Modified

Mar 27, 2026

Description

An issue present in lowering/register allocation could have led to obscure but deterministic register confusion failures in JITted code that would lead to a potentially exploitable crash. This vulnerability affects Firefox < 91 and Thunderbird < 91.

Solution

mozilla-thunderbird-upgrade-91_0

References

CVE-2021-29981
https://attackerkb.com/topics/CVE-2021-29981
EUVD-EUVD-2021-16440
http://www.mozilla.org/security/announce/2021/mfsa2021-36.html
https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-16440

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