CVE-2026-9177
A Server-Side Template Injection (SSTI) vulnerability was identified in the mail template functionality of the Axway SecureTransport product in version 5.5-20260326. This flaw allows an attacker with admin privileges to inject arbitrary Java code expressions, which are executed server-side when the template is rendered (i.e., during email sending). Successful exploitation of this flaw allows an attacker to execute arbitrary code on the server that results in full host compromise. This issue affects all Axway SecureTransport versions prior 5.5-20260528 update.
No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 4.0 : 9.4 CRITICAL
Vector: AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.