CVE-2021-43539

Name of the Vulnerable Software and Affected Versions Thunderbird versions prior to 91.4.0 Firefox ESR versions prior to 91.4.0 Firefox versions prior to 95

Description The issue is related to the incorrect recording of live pointers across wasm instance calls, leading to a garbage collection (GC) that does not trace these live pointers. This could result in a use-after-free, causing a potentially exploitable crash. The vulnerability can be exploited by a remote attacker using a specially crafted web page, potentially allowing the execution of arbitrary code.

Recommendations For Thunderbird versions prior to 91.4.0, update to version 91.4.0 or later. For Firefox ESR versions prior to 91.4.0, update to version 91.4.0 or later. For Firefox versions prior to 95, update to version 95 or later.