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vulnerability

Red Hat: CVE-2021-29984: CVE-2021-29984 Mozilla: Incorrect instruction reordering during JIT optimization (Multiple Advisories)

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Aug 16, 2021
Added
Aug 17, 2021
Modified
Mar 27, 2026

Description

Instruction reordering resulted in a sequence of instructions that would cause an object to be incorrectly considered during garbage collection. This led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.

Solutions

redhat-upgrade-firefoxredhat-upgrade-firefox-debuginforedhat-upgrade-firefox-debugsourceredhat-upgrade-thunderbirdredhat-upgrade-thunderbird-debuginforedhat-upgrade-thunderbird-debugsource

References

    Title
    Rapid7 Labs

    2026 Global Threat Landscape Report

    The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.