CVE-2026-12294

Sandbox escape in the DOM: Workers component

Critical · published June 16, 2026

CVSS v3.1
9.6
EPSS
0%
Percentile
28.9
In the wild
Unconfirmed
What it is

Sandbox escape in the DOM: Workers component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

The record
Technical detail
CVSS v3.1
9.6 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00363 · 28.9th percentile
Published
2026-06-16T11:52Z
EPSS history
Timeline
  • 16 JUN 11:52Z
    Sandbox escape in the DOM: Workers component
    cvelistv5