Vulnerability · Published Sep 29, 2026 · Assigned by Joomla

CVE-2026-90918Joomla! Core - [20260908] - Core - XSS in HTML Mail Templates in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3

Medium 6.9

In plain English

A medium-severity cross-site scripting in Joomla! CMS from Joomla! Project. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 10% of all known vulnerabilities).

Severity (CVSS 4.0)6.9Medium
Exploit odds (30 days)0.2%top 89.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Joomla! Core - [20260908] - Core - XSS in HTML Mail Templates in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3 - The mail template feature lacks an escaping mechanism, causing XSS vectors in multiple extensions.

Affected products (as reported)

VendorProductVersions
Joomla! Project Joomla! CMS 4.0.0-5.4.86.0.0-6.1.3

Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

References