Vulnerability · Published May 8, 2026 · Assigned by NCSC.ch

CVE-2026-44129Server-side template injection

High 8.3

In plain English

A high-severity security flaw in Secure Email Gateway from SEPPmail AG. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities).

Severity (CVSS 4.0)8.3High

Exploit odds (30 days)0.5%top 54.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

SEPPmail Secure Email Gateway before version 15.0.4 contains a server-side template injection vulnerability in the new GINA UI because an endpoint accepts attacker-controlled template, allowing remote attackers to execute arbitrary template expressions and potentially achieve remote code execution depending on the enabled template plugins.

Affected products (as reported)

Vendor	Product	Versions
SEPPmail AG	Secure Email Gateway	0 – before 15.0.4

Weakness: CWE-1336 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N

In plain English

Official description

Affected products (as reported)

References