OpenCVE

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

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact Low

Subsequent System Integrity Impact High

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Seppmail	Seppmail Secure Email Gateway

No data.

No data.

References

Link	Providers
https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure

History

Wed, 04 Mar 2026 17:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Wed, 04 Mar 2026 09:15:00 +0000

Type	Values Removed	Values Added
Description		SEPPmail Secure Email Gateway before version 15.0.1 improperly validates S/MIME certificates issued for email addresses containing whitespaces, allowing signature spoofing.
Title		S/MIME Certificate Subject Whitespace
First Time appeared		Seppmail Seppmail seppmail Secure Email Gateway
Weaknesses		CWE-295
CPEs		cpe:2.3:a:seppmail:seppmail_secure_email_gateway::::::::
Vendors & Products		Seppmail Seppmail seppmail Secure Email Gateway
References		https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure
Metrics		cvssV4_0 `{'score': 7.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N'}`

MITRE

Status: PUBLISHED

Assigner: NCSC.ch

Published: 2026-03-04T08:48:58.786Z

Updated: 2026-03-04T16:55:03.279Z

Reserved: 2026-02-19T13:56:33.534Z

Link: CVE-2026-2748

Vulnrichment

Updated: 2026-03-04T16:54:59.084Z

NVD

Status : Awaiting Analysis

Published: 2026-03-04T09:15:58.290

Modified: 2026-03-04T18:08:05.730

Link: CVE-2026-2748

Redhat

No data.

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