Without knowing the contents of the page nobody can possibly tell you if it's a false alarm or a legitimate issue. In either case, path disclosure is the result of a bug in the software running on your site, causing a full filesystem path to be displayed in the page's contents. Typically it's the result of a bug in the software and your Error Reporting in Global Configuration set to a value other than None. In this case PHP prints out an error message which includes the full filesystem path to the file where the error occurred.
Even so, your issue is unrelated to our software or the .htaccess file that you sent us. We are not responsible for third party software's bugs or your server's error reporting settings. The only two valid mitigations are 1. set the error reporting to None (the ONLY recommended value for live sites) and 2. find the problem causing the PHP error that's being printed out and contact its developer about a fix.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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