CVE-2026-29138: Seppmail Secure Email Gateway

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

SEPPmail Secure Email Gateway before version 15.0.3 allows attackers with a specially crafted email address to claim another user's PGP signature as their own.

Affected products

• Seppmail Secure Email Gateway: before 15.0.3 (fixed in 15.0.3)

Published 2026-04-02. Last modified 2026-06-17.