If you found ninjamailer.php in your site's directory and did not put it there:
: It is designed to mass-send emails, often bypassing standard server restrictions to facilitate phishing or malware proliferation. ninjamailer.php
It is important to distinguish this script from legitimate WordPress plugins that use similar names: If you found ninjamailer
The file ninjamailer.php is most commonly associated with a used by cyberattackers to send spam or malicious content. Specifically, a tool named TeamCC ninjaMailer v1.3.3 has been identified by security researchers at Talos Intelligence as part of the toolsets used in targeted cyber campaigns to distribute malicious documents and download links. Common Characteristics Common Characteristics : Legitimate tools used for improving
: Legitimate tools used for improving email deliverability or verifying email lists . Recommended Actions
: Check your server logs to see when the file was uploaded and from what IP address.