High 7.8Published Mar 4, 2026

CVE-2026-2748S/MIME Certificate Subject Whitespace

Updated under an hour ago (Oct 26, 2026, 3:00 PM ET)

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It affects SEPPmail Secure Email Gateway and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for SEPPmail Secure Email Gateway

Exploited in the last 30 days

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

CVSS: 7.8 HIGH (v4.0, CNA)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
Weakness (CWE): CWE-295
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: NCSC.ch
NVD analysis: Analyzed
Record last updated: Mar 4, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

SEPPmail Secure Email Gateway seppmail:secure_email_gateway (from the name)	before 15.0.1	CNA record
seppmail seppmail seppmail:seppmail	before 15.0.1	NVD

References

References

https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure	release-notes, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.