/civicrm/civicrm/CRM/Case/BAO/Query.php Reported to Contain Malware by Wordfence
No, this is a false positive.

The line flagging this is:


  $from .= " $side JOIN civicrm_option_value recent_activity_medium ON
  (case_activity.medium_id = recent_activity_medium.value AND
  option_group_activity_medium.id =
  recent_activity_medium.option_group_id ) ";


Suggested courses of action:
1. Get rid of Wordfence.
2. Tell Wordfence about this false positive and request they fix it.