Exchange Online

Reported Context (2)

The change will begin rolling out to Exchange Online users in early November, when the new file types will be added to the BlockedFileTypes list in all OWA Mailbox policies, and is expected to reach general availability Outlook to Block MSIX Attachments Starting in November
multiple attempts of this security control bypass for RejectDirectSend, a Microsoft 365 control in Exchange Online intended to block unauthenticated Direct Send emails from an organization’s domain. Empty SMTP Sender Can Bypass Microsoft 365 RejectDirectSend Control

People (2)

MITRE ATT&CK (1)

Vendors (2)

Products (6)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.