vulnerability
MFSA2021-49 Firefox: Security Vulnerabilities fixed in Firefox ESR 91.3 (CVE-2021-43534)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Nov 2, 2021 | Dec 8, 2021 | Mar 27, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Nov 2, 2021
Added
Dec 8, 2021
Modified
Mar 27, 2026
Description
Mozilla developers and community members reported memory safety bugs present in Firefox 93 and Firefox ESR 91.2. 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 Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.
Solution
mozilla-firefox-esr-upgrade-91_3
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