Headline
GHSA-68q5-78xp-cwwc: Contao is vulnerable to cross-site scripting in templates
Impact
It is possible to inject code into the template output that will be executed in the browser in the front end and back end.
Patches
Update to Contao 4.13.57, 5.3.42 or 5.6.5.
Workarounds
Do not use the affected templates or patch them manually.
Refsources
https://contao.org/en/security-advisories/cross-site-scripting-in-templates
Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.