Details
By performing filtering at the perimeter, up to 90 percent of spam, malware, and other undesirable messages are eliminated from the message stream rather than admitting them into the mail server environment. Anonymous email (messages with blank sender fields) cannot be replied to. Messages formatted in this way may be attempting to hide their true origin to avoid responses or to spam any receiver with impunity while hiding their source of origination.
Rather than spend resources and risk infection while evaluating them, it is recommended that these messages be filtered immediately upon receipt and not forwarded to end users.
Solution
Open the Exchange Management Shell and enter the following command:
Set-SenderFilterConfig -Action Reject
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: System and Information Integrity.This control applies to the following type of system Windows.
References
- 800-53|SI-8(2)
- CAT|II
- CCI|CCI-001308
- Rule-ID|SV-221232r612603_rule
- STIG-ID|EX16-ED-000330
- STIG-Legacy|SV-95255
- STIG-Legacy|V-80545
- Vuln-ID|V-221232