CVE-2026-16355

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 153 Firefox ESR versions prior to 115.38 Firefox ESR versions prior to 140.13 Thunderbird versions prior to 153 Thunderbird version prior to 140.13

Description A JIT miscompilation issue exists within the JIT component of the JavaScript Engine. JIT (Just-In-Time) compilation is a method used by the engine to improve performance by compiling code during execution rather than before.

Recommendations Update Firefox to version 153 or later. Update Firefox ESR to version 115.38 or later. Update Firefox ESR to version 140.13 or later. Update Thunderbird to version 153 or later. Update Thunderbird to version 140.13 or later.