Rapid7

vulnerability

Debian: CVE-2025-5263: firefox-esr, thunderbird -- security update

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:N)
Published
May 27, 2025
Added
May 29, 2025
Modified
Apr 15, 2026

Description

Error handling for script execution was incorrectly isolated from web content, which could have allowed cross-origin leak attacks. This vulnerability was fixed in Firefox 139, Firefox ESR 115.24, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.

Solutions

debian-upgrade-firefox-esrdebian-upgrade-thunderbird
Title
Rapid7 Labs

2026 Global Threat Landscape Report

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