CVE-2026-27443: Seppmail

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

SEPPmail Secure Email Gateway before version 15.0.1 does not properly sanitize the headers from S/MIME protected MIME entities, allowing an attacker to control trusted headers.

Affected products

• Seppmail Seppmail: before 15.0.1 (fixed in 15.0.1)

Published 2026-03-04. Last modified 2026-06-17.