After scanneing, I get 3 HIGH SEVERITY files. The system itself says: "required file - uwe clean, not delete". So I selct the file (index.php), and click the "clean selected"-button.

reason: Core file checksum mismatch — this file's content does not match the official Joomla 5.4.7 release byte-for-byte (expected sha256 bba2171c2b43…, found 760340df54e7…). This is direct, unambiguous evidence of tampering, not a heuristic guess.

error code: SKIPPED (no auto-cleanable pattern recognized here -- review the Code Issues details and clean manually): index.php