vulnerability

MFSA2021-53 Firefox: Security Vulnerabilities fixed in Firefox ESR 91.4.0 (CVE-2021-43539)

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Severity

CVSS

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

Published

Dec 7, 2021

Added

Dec 8, 2021

Modified

Mar 27, 2026

Description

Failure to correctly record the location of live pointers across wasm instance calls resulted in a GC occurring within the call not tracing those live pointers. This could have led to a use-after-free causing a potentially exploitable crash. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Solution

mozilla-firefox-esr-upgrade-91_4

References

CVE-2021-43539
https://attackerkb.com/topics/CVE-2021-43539
CWE-416
EUVD-EUVD-2021-30468
http://www.mozilla.org/security/announce/2021/mfsa2021-53.html
https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-30468

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