Rapid7

vulnerability

MFSA2025-15 Firefox: Security Vulnerabilities fixed in Firefox ESR 115.21 (CVE-2025-1931)

Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Mar 4, 2025
Added
Mar 5, 2025
Modified
Apr 15, 2026

Description

It was possible to cause a use-after-free in the content process side of a WebTransport connection, leading to a potentially exploitable crash. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

Solution

mozilla-firefox-esr-upgrade-115_21
Title
Rapid7 Labs

2026 Global Threat Landscape Report

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