Scanner says core files were modified? Open the diff. After wp2shell, that is often leftover access.

How to read it

Malware scanner

Scan WordPress

Run a Core Scanner check on your WordPress installation. Live results, severity levels, and File Viewer actions.

To scan your core WordPress files, go to Security Ninja → Core Scanner and click Scan Core Files.

Core Scanner tab with Scan Core Files button

A progress overlay runs while the plugin fetches the official file list from wordpress.org for your WordPress version and locale, then compares checksums locally. Most scans finish in under a minute.

Reading results

The summary strip shows scan context, status, and last-run metadata. Findings appear in a table grouped by type (modified, missing, unknown) with severity, guidance, and actions.

You can View File, open a diff for modified core files, Restore, Delete, or mark files to ignore without leaving the page.

Large or binary-safe previews open in the File Viewer.

What gets scanned

Security Ninja checks standard core paths, including:

  • Files under wp-admin and wp-includes
  • Expected and unexpected files in the WordPress root
  • Hidden dotfiles in core directories

There are well over a thousand core files in a typical install. Each one is verified against the official manifest.

My developer modified core files

That is not always malicious. Some hosts or legacy setups still touch core files. Unless you know why a file changed, treat unexpected modifications as a risk and review them in the File Viewer before restoring or deleting.

Note: If you re-install WordPress, manual core edits are overwritten. Confirm with your developer before restoring from the scanner.

Keep WordPress updated. Core updates include security fixes that plugins and themes may depend on.

Still stuck? Get help or contact us.

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