Access to Web-UI results in Internal Server Error (Issues with saml)

Nextcloud version: 24.0.5.1
Operating system and version: Ubuntu 20.04.2 LTS
nginx version: openresty/1.19.3.1
PHP version: 8.0.23

My Nextcloud has been running without issues for a while. I’m running it using docker-compose/docker images.
Now (without any interaction I’m aware of) when I want to access the web UI I get an internal server error and no further interaction on web UI is possible.

Nevertheless I’m still able to access the files using the desktop app. Also the calendar runs without issues. It’s only that I can’t access the web UI anymore.

I was even able to upgrade to a new version (24.0.5.1). But that didn’t change anything in the observed behaviour.

In the Nextcloud log I find two entries for the request id given in the screenshot above. Both indicate an exception

"Exception": "Error",
"Message": "foreach() argument must be of type array|object, null given at /var/www/html/apps/user_saml/lib/SAMLSettings.php#116",
"Exception": "OneLogin\\Saml2\\Error",
"Message": "Invalid array settings: idp_entityId_not_found, idp_sso_not_found, idp_cert_or_fingerprint_not_found_and_required",

Any help would be appreciated very much. Thx :slight_smile: