Quttera Error message

Hi
Can you can firm this is a error message that can be whitelisted from your code for a possible threat?

Severity:	enMaliciousThreatType
File:	wp-content/plugins/newsletter/emails/emails.php
File signature:	6c439172341649c6d3cc55afe6dcf8cd
Threat signature:	503491dd6565c0093803a6e65342d755
Threat name:	Heur.PHP.Encoded.gen
Threat:	$_REQUEST['b']...
Details:	Detected malicious PHP REQUEST