It is possible to inject code into the template output that will be executed in the browser in the front end and back end.
Update to Contao 4.13.57, 5.3.42 or 5.6.5.
Do not use the affected templates or patch them manually.
https://contao.org/en/security-advisories/cross-site-scripting-in-templates
{
"nvd_published_at": "2025-11-25T19:15:51Z",
"github_reviewed_at": "2025-11-25T20:48:13Z",
"severity": "LOW",
"github_reviewed": true,
"cwe_ids": [
"CWE-87"
]
}