T1027 Obfuscated Files or Information Mappings

In Microsoft 365 organizations with mailboxes in Exchange Online or standalone Exchange Online Protection (EOP) organizations without Exchange Online mailboxes, email messages are automatically protected against malware by EOP. Some of the major categories of malware are: Viruses that infect other programs and data, and spread through your computer or network looking for programs to infect. Spyware that gathers your personal information, such as sign-in information and personal data, and sends it back to its author. Ransomware that encrypts your data and demands payment to decrypt it. Anti-malware software doesn't help you decrypt encrypted files, but it can detect the malware payload that's associated with the ransomware. EOP offers multi-layered malware protection that's designed to catch all known malware in Windows, Linux, and Mac that travels into or out of your organization. The following options help provide anti-malware protection: Layered defenses against malware: Multiple anti-malware scan engines help protect against both known and unknown threats. These engines include powerful heuristic detection to provide protection even during the early stages of a malware outbreak. This multi-engine approach has been shown to provide significantly more protection than using just one anti-malware engine. Real-time threat response: During some outbreaks, the anti-malware team might have enough information about a virus or other form of malware to write sophisticated policy rules that detect the threat, even before a definition is available from any of the scan engines used by the service. These rules are published to the global network every 2 hours to provide your organization with an extra layer of protection against attacks. Fast anti-malware definition deployment: The anti-malware team maintains close relationships with partners who develop anti-malware engines. As a result, the service can receive and integrate malware definitions and patches before they're publicly released. Our connection with these partners often allows us to develop our own remedies as well. The service checks for updated definitions for all anti-malware engines every hour. License Requirements: M365 E3 or Microsoft Defender for Office plan 1.

Zero-hour auto purge (ZAP) is a protection feature in Exchange Online Protection (EOP) that retroactively detects and neutralizes malicious phishing, spam, or malware messages that have already been delivered to Exchange Online mailboxes. With the E5 licensing or Office Plan 2, ZAP is also able to retroactively detect existing malicious chat messages in Microsoft Teams that are identified as malware or high confidence phishing. License Requirements: ZAP for Defender O365 is included with M365's E3 and requires E5 when leveraging ZAP for Teams security.

In Exchange Online Protection (EOP) and Microsoft Defender for Office 365, quarantine policies allow admins to define the user experience for quarantined messages. Traditionally, users have been allowed or denied levels of interactivity with quarantine messages based on why the message was quarantined. For example, users can view and release messages that were quarantined as spam or bulk, but they can't view or release messages that were quarantined as high confidence phishing or malware. The following M365 features are supported by quarantine policies, “Response” to Anti-malware and Anti-Phishing tagged items. Files that are quarantined as malware by Safe Attachments for SharePoint, OneDrive, and Microsoft Teams. License requirements: M365 E3 (or Defender for Office plan 1)