CVE-2026-29143 — S/MIME Decryption Impersonation

CVE-2026-29143

S/MIME Decryption Impersonation PUBLISHED

Description (CNA)

SEPPmail Secure Email Gateway before version 15.0.3 does not properly authenticate the inner message of S/MIME-encrypted MIME entities, allowing an attacker to control trusted headers.

Affected (CNA)

Vendor / product	Versions
SEPPmail / Secure Email Gateway	affected 0 before 15.0.3

CWE

CWE-20

References

https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure-1503

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.