Email Gateway Subject Sanitization Bypass in SEPPmail
CVE-2026-29141

7.7HIGH

Key Information:

Vendor

Seppmail

Status
Secure Email Gateway
Vendor
CVE Published:
2 April 2026

What is CVE-2026-29141?

The SEPPmail Secure Email Gateway prior to version 15.0.3 is susceptible to a subject sanitization bypass vulnerability. This issue enables attackers to manipulate email subjects by forging tags, such as [signed OK], potentially leading to misrepresentation and increased risk of phishing attacks.

Affected Version(s)

Secure Email Gateway 0 < 15.0.3

References

https://downloads.seppmail.com/extrelnotes/150/ERN15.0.ht...
release-notes

CVSS V4

Score:
7.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Andris Suter-Dörig
Matteo Scarlata
Kenny Paterson
.