Office 365 Advanced Threat Protection (ATP)
Advanced Threat Protection (ATP) extends our existing Exchange Online Protection Service (which provides email protection against spam, viruses and malware) by offering 2 additional services: Safe Attachments and Safe Links.
Safe Attachments
This feature checks message attachments for malware and removes them if they test positive. Unsafe attachments are removed while the body of the message continues on to the recipient. If an attachment is deemed unsafe and removed, the system will substitute a text file named “Malware Alert Text.txt” alerting the recipient that an unsafe attachment was found and removed. It will include the file name/type as well.
Safe Links
ATP’s Safe Links feature proactively protects users from malicious hyperlinks in a message. The protection remains every time a user clicks the link, as malicious links are dynamically blocked while good links can be accessed. NOTE: you will notice that the URL for links in your email are rewritten to have the path https://…safelinks.protection.outlook.com… This allows the links to be filtered through Microsoft’s Safe Links engine.