CVE-2026-2748

SEPPmail Secure Email Gateway before version 15.0.1 improperly validates S/MIME certificates issued for email addresses containing whitespaces, allowing signature spoofing.

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	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

05 Mar 2026, 15:14

Type	Values Removed	Values Added
References	~~() https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure -~~	() https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3
First Time		Seppmail Seppmail seppmail
CPE		cpe:2.3:a:seppmail:seppmail::::::::

04 Mar 2026, 09:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-04 09:15

Updated : 2026-03-05 15:14

NVD link : CVE-2026-2748

Mitre link : CVE-2026-2748

CVE.ORG link : CVE-2026-2748

JSON object : View

Products Affected

seppmail

seppmail

CWE

CWE-295

Improper Certificate Validation

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