Detection of phishing messages in network communications is performed by receiving a transmitted message and detecting characteristics of the message. A determination is made if the message matches a pattern of a phishing message in a database, and classifies the message as a phishing or spam message accordingly. If the message does not match a known phishing message pattern, the message is checked for common signs of phishing or spam by determining the severity of a threat embodied by the message, and the message is categorized as having phishing characteristics and according to the severity of threat. In response the user responses to determinations of threats, criteria for detection of phishing characteristics is adjusted, thereby automatically revising criteria for future decisions as to whether the message represents suspected phishing.