CVE-2026-29140

SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificates to be used for future encryption to a victim by adding the certificates to S/MIME signatures.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

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

No history.

Information

Published : 2026-04-02 09:16

Updated : 2026-06-17 10:29

NVD link : CVE-2026-29140

Mitre link : CVE-2026-29140

CVE.ORG link : CVE-2026-29140

JSON object : View

Products Affected

seppmail

secure_email_gateway

CWE

CWE-295

Improper Certificate Validation

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