WordPress shows homepage instead of 404

I’m currently running into a strange problem with WordPress on my production server. When I try to visit non-existing URLs, WordPress doesn’t trigger a 404 when the url has more than 3 segments, for example:

These trigger a 404 page:

• https://example.com/9
• https://example.com/9/9

These don’t trigger a 404 page and show the homepage (with 200 response code):

• https://example.com/9/9/9
• https://example.com/9/9/9/9
• https://example.com/9/9/9/9/9

On my local machine all above pages show a 404 (as expected), the server however doesn’t. The server (and my local machine) are both running nginx >10.16, both nginx vhost configs are almost equal. Running PHP72-fpm.

Debugging I already did:

• Disable functions.php in theme folder
• Disable all plugins
• Switch to other theme
• Disable cloudflare caching
• Flush permalinks

All without any success unfortunately.. I’m kinda running out of options for debugging, I hope anyone has got any suggestions!

• This topic was modified 5 years, 4 months ago by roboonl.
• This topic was modified 5 years, 4 months ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Everything else WordPress topic