Rendering spoofed electronic mail harmless

Abstract

An obscuration key is associated with each domain served by a group of trusted servers, and is used when sending and receiving all emails between the trusted servers. An e-mail server attempts to reverse the presumed obscuration of the body of an e-mail message prior to delivering the message to the intended recipient. If the obscuration key and method have been previously applied to the body of a message, reversal restores the body of the message such that the recipient receives precisely the message intended by the sender. If the obscuration method has not been previously applied to the content of the message, the reversal is destructive in that the body of the message is unreadable, including any URLs and URL links in the body of the message and any binary attachments to the message. Any attempt to spoof the sender without (i) use of the particular e-mail server the spoofed sender would use and (ii) authentication as the spoofed sender with that e-mail server is destructively obscured when received by the recipient. With any and all URLs and URL links in the body of the message destroyed, the recipient is prevented from reaching any harm intended by the message. With any binary attachments destroyed, the recipient is prevented from launching any malware attached to the message. Any phishing attempt resulting from the spoofing is completely thwarted.