CVE-2026-27443

High

Description

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.

SeverityHigh

CVSS7.5

Exploit probability—

ProductSeppmail

PublishedMar 4, 2026

First seenMar 4, 2026

Weakness typeCWE-20Improper input validation

How to fix

Update

seppmail seppmail15.0.1 or later

Vendor advisories

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

Affected products

Product	Affected versions	Fixed in
seppmail seppmail	v < 15.0.1	15.0.1

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