CVE-2026-27064: Everpress Mailster

Critical severity, CVSS 9.1. EPSS: 0.5% chance of exploitation in the next 30 days.

Editor Arbitrary File Upload in Mailster <= 4.1.17 versions.

Affected products

• Everpress Mailster: up to and including 4.1.17

Published 2026-07-23. Last modified 2026-07-23.