Improper HTML sanitization in ZITADEL

Impact

ZITADEL uses Go templates to render the login UI.

Due to a improper use of the text/template instead of the html/template package, the Login UI did not sanitize input parameters. An attacker could create a malicious link, where he injected code which would be rendered as part of the login screen.
While it was possible to inject HTML including javascript, the execution of such scripts would be prevented by the Content Security Policy.

Patches

2.x versions are fixed on >= 2.47.3
2.46.x versions are fixed on >= 2.46.1
2.45.x versions are fixed on >= 2.45.1
2.44.x versions are fixed on >= 2.44.3
2.43.x versions are fixed on >= 2.43.9
2.42.x versions are fixed on >= 2.42.15
2.41.x versions are fixed on >= 2.41.15

ZITADEL recommends upgrading to the latest versions available in due course.

Workarounds

There is no workaround since a patch is already available.

Questions

If you have any questions or comments about this advisory, please email us at [email protected]

Credits

Thanks to Daniel Philipp - owt and Thomas Wickham - synopsis for reporting this.