Mozilla has released security updates to address security vulnerabilities in Firefox and Thunderbird. An attacker could exploit some of these vulnerabilities to trigger security restriction bypass, sensitive information disclosure and denial of service condition on the targeted system. Security vulnerabilities fixed in Firefox 147.0.2, Thunderbird 140.7.1 and Thunderbird 147.0.1.

More information on vulnerabilities and updates is available in Mozilla security advisories:

• MFSA 2026-08

• MFSA 2026-07

• MFSA 2026-06