The Mailbox server is not protected by having blank sender messages filtered by the Edge Transport Role server (E-mail Secure Gateway) at the perimeter.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-18674	EMG2-026 Exch2K3	SV-20292r1_rule	ECSC-1	Medium

Description
By performing filtering at the perimeter, up to 90% of SPAM, malware, and other undesirable messages are eliminated from the message stream rather than admitting them into the mail server environment. Anonymous E-mail (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 resource and risk infection while evaluating them, it is recommended that these messages be filtered immediately upon receipt and not forwarded to end users.

Description

By performing filtering at the perimeter, up to 90% of SPAM, malware, and other undesirable messages are eliminated from the message stream rather than admitting them into the mail server environment. Anonymous E-mail (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 resource and risk infection while evaluating them, it is recommended that these messages be filtered immediately upon receipt and not forwarded to end users.

STIG	Date
Microsoft Exchange Server 2003	2014-08-19

Details

Check Text ( C-22393r1_chk )
Interview the E-mail Administrator or the IAO. Request documentation that indicates Messages with blank senders are filtered at the perimeter by an Edge Tranport Server role (E-mail Secure Gateway). Criteria: If inbound messages with blank sender are filtered and archived, this is not a finding.

Fix Text (F-19321r1_fix)
Implement perimeter-based protection in the form of an Edge Transport Role server (E-mail Secure Gateway) filtering mechanism that performs, among other protections, filtering messages with blank sender and archiving them for SPAM elimination.