CVE-2026-29143

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.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

cpe:2.3:a:seppmail:secure_email_gateway:*:*:*:*:*:*:*:*

History

16 Apr 2026, 18:58

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.1
CPE		cpe:2.3:a:seppmail:secure_email_gateway::::::::
References	~~() https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure-1503 -~~	() https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure-1503 - Release Notes
First Time		Seppmail Seppmail secure Email Gateway

02 Apr 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-02 09:16

Updated : 2026-04-16 18:58

NVD link : CVE-2026-29143

Mitre link : CVE-2026-29143

CVE.ORG link : CVE-2026-29143

JSON object : View

Products Affected

seppmail

secure_email_gateway

CWE

CWE-20

Improper Input Validation

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