CVE-2026-2748 HIGH

CVE-2026-2748: S/MIME Certificate Subject Whitespace

Vendor Seppmail
Product Secure Email Gateway
Weakness CWE-295
Published March 4, 2026
Last update March 4, 2026
View on NVD All CVEs

CVSS base score

7.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS 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

What the vulnerability does

01Description

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

Key dates

02Disclosure timeline

March 4, 2026 CVE published
March 4, 2026 Record updated