Rapid7

vulnerability

MFSA2026-30 Firefox: Security Vulnerabilities fixed in Firefox 150 (CVE-2026-6755)

Severity
7
CVSS
(AV:N/AC:L/Au:S/C:N/I:N/A:C)
Published
Apr 21, 2026
Added
Apr 23, 2026
Modified
Apr 27, 2026

Description

Mitigation bypass in the DOM: postMessage component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Solution

mozilla-firefox-upgrade-150_0
Title
Rapid7 Labs

2026 Global Threat Landscape Report

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