vulnerability
MFSA2021-50 Thunderbird: Security Vulnerabilities fixed in Thunderbird 91.3 (CVE-2021-43535)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Nov 3, 2021 | Dec 8, 2021 | Mar 27, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Nov 3, 2021
Added
Dec 8, 2021
Modified
Mar 27, 2026
Description
A use-after-free could have occured when an HTTP2 session object was released on a different thread, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 93, Thunderbird < 91.3, and Firefox ESR < 91.3.
Solution
mozilla-thunderbird-upgrade-91_3
Rapid7 Labs
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