CVE-2025-8029: Mozilla Firefox

High severity, CVSS 8.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Thunderbird executed `javascript:` URLs when used in `object` and `embed` tags. This vulnerability was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

Affected products

• Mozilla Firefox: before 128.13.0 (fixed in 128.13.0); before 141.0 (fixed in 141.0); from 140.0, before 140.1.0 (fixed in 140.1.0)
• Mozilla Thunderbird: before 128.13.0 (fixed in 128.13.0); before 141.0 (fixed in 141.0); from 140.0, before 140.1.0 (fixed in 140.1.0)

Published 2025-07-22. Last modified 2026-09-30.