CVE-2026-2764

JIT miscompilation, use-after-free in the JavaScript Engine: JIT component

Critical · published February 24, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
52.1
In the wild
Unconfirmed
What it is

JIT miscompilation, use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00685 · 52.1th percentile
Published
2026-02-24T13:33Z
EPSS history
Timeline
  • 24 FEB 13:33Z
    JIT miscompilation, use-after-free in the JavaScript Engine: JIT component
    cvelistv5