CVE-2025-10533: Mozilla Firefox

High severity, CVSS 8.8. EPSS: 0.8% chance of exploitation in the next 30 days.

Integer overflow in the SVG component. This vulnerability was fixed in Firefox 143, Firefox ESR 115.28, Firefox ESR 140.3, Thunderbird 143, and Thunderbird 140.3.

Affected products

• Mozilla Firefox: before 115.28.0 (fixed in 115.28.0); before 143.0 (fixed in 143.0); from 116.0, before 140.3 (fixed in 140.3)
• Mozilla Thunderbird: before 140.3.0 (fixed in 140.3.0); from 141.0, before 143.0 (fixed in 143.0)

Published 2025-09-16. Last modified 2026-06-17.