PT-2026-29706 · Seppmail · Secure Email Gateway

Andris Suter-Dörig + 2 · Published 2026-04-02 · Updated 2026-04-02 · CVE-2026-29143

Mitre

CVSS v4.0

7.8

High

AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N

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.

Fix

RCE

Weakness Enumeration

CWE-20

Related Identifiers

CVE-2026-29143

Affected Products

Secure Email Gateway

References · 2

• https://nvd.nist.gov/vuln/detail/CVE-2026-29143 · Security Note
• https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure-1503 · Note