vulnerability

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

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Dec 7, 2021
Added
Dec 8, 2021
Modified
Aug 11, 2025

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
Title
NEW

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