CVE-2026-74956

Published Aug 18, 2026

Last updated 6 days ago

Overview

Description
Same-origin policy bypass in the DOM: Service Workers component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
Source
security@mozilla.org
NVD status
Analyzed
Products
firefox, thunderbird

Risk scores

CVSS 3.1

Type
Secondary
Base score
9.1
Impact score
5.2
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity
CRITICAL

Weaknesses

134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-843

Social media

Hype score
Not currently trending

Configurations