CVE-2026-2766

Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Affected products

Firefox, Firefox Esr, Rocky Linux, Thunderbird

Mozilla Firefox

< 140.8.0, 148.0

Mozilla Thunderbird

< 140.8.0, 148.0

CVSS 3.1

9.8 CRITICAL

EPSS

0.5% (38th percentile)

Weakness

CWE-416

NVD status

Modified

Published

2026-02-24