CVE-2026-84831

High

Description

SEPPmail Secure Email Gateway before 15.0.7 creates a fully privileged session before required multi-factor authentication enrollment is completed. An attacker with the password for an MFA-required but unenrolled account can access protected functionality without providing a second factor.

SeverityHigh

CVSS7.7

Exploit probability—

ProductSEPPmail Secure Email Gateway (SEG)

PublishedSep 3, 2026

First seenSep 3, 2026

Weakness typeCWE-287Improper authentication CWE-306Missing authentication for critical function

How to fix

Update

SEPPmail AG SEPPmail Secure Email Gateway (SEG)15.0.7 or later

Affected products

Product	Affected versions	Fixed in
SEPPmail AG SEPPmail Secure Email Gateway (SEG)	v < 15.0.7	15.0.7

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