CVE-2026-12321

JIT miscompilation in the JavaScript: WebAssembly component

Medium · published June 16, 2026

CVSS v3.1
5.4
EPSS
0%
Percentile
4.7
In the wild
Unconfirmed
What it is

JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.

The record
Technical detail
CVSS v3.1
5.4 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00159 · 4.7th percentile
Published
2026-06-16T11:52Z
EPSS history
Timeline
  • 16 JUN 11:52Z
    JIT miscompilation in the JavaScript: WebAssembly component
    cvelistv5