Public Folder access does not require secure channels and encryption.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-18786	EMG1-103 Exch2K3	SV-20498r1_rule	ECCT-1	High

Description
Failure to require secure connections on a web site increases the potential for unintended decryption and data loss. This setting controls whether client machines should be forced to use secure channels to communicate with this virtual directory. If this feature is enabled, clients will only be able to communicate with the directory if they are capable of supporting secure communication with the server. If secure channels are required, the server can also require the channel to be strongly secured by requiring Federal Information Processing Standard (FIPS) 140-2 encryption. If Public Folders / Web is approved for use, secure channels and FIPS level encryption are required, as well as appropriate certificate setting. The use of secure communication prevents eavesdroppers from reading or modifying communications between servers and clients. The network and DMZ STIG identify criteria for OWA and Public Folder configuration in the network, including CAC enabled pre-authentication through an application firewall proxy, such as Microsoft ISA. Note: if Public Folder is not approved for use, this control is not applicable and the Public Folder virtual directory should be removed to eliminate the possibility of attack through this vector.

Description

Failure to require secure connections on a web site increases the potential for unintended decryption and data loss. This setting controls whether client machines should be forced to use secure channels to communicate with this virtual directory. If this feature is enabled, clients will only be able to communicate with the directory if they are capable of supporting secure communication with the server. If secure channels are required, the server can also require the channel to be strongly secured by requiring Federal Information Processing Standard (FIPS) 140-2 encryption. If Public Folders / Web is approved for use, secure channels and FIPS level encryption are required, as well as appropriate certificate setting. The use of secure communication prevents eavesdroppers from reading or modifying communications between servers and clients. The network and DMZ STIG identify criteria for OWA and Public Folder configuration in the network, including CAC enabled pre-authentication through an application firewall proxy, such as Microsoft ISA. Note: if Public Folder is not approved for use, this control is not applicable and the Public Folder virtual directory should be removed to eliminate the possibility of attack through this vector.

STIG	Date
Microsoft Exchange Server 2003	2014-08-19

Details

Check Text ( C-22496r1_chk )
If Public Folders are not in use at the site, the web directory should be deleted, and this check becomes N/A. Validate Public Folder Web Security. Procedure: IIS Manager>> [Server name]>>Web Sites>>Default Web Site >> PUBLIC >>Properties >> Directory Security tab >> Secure Communications >> Edit button Secure Channel and 128 bit Encryption should be selected. Under "Client Certificates", the "ignore client certificates" option should be selected. All other checkboxes should be cleared. Criteria: If "Secure Channel" and "128 bit Encryption" are selected, with "ignore client certificates", this is not a finding.

Check Text ( C-22496r1_chk )

If Public Folders are not in use at the site, the web directory should be deleted, and this check becomes N/A.

Validate Public Folder Web Security.

Procedure: IIS Manager>> [Server name]>>Web Sites>>Default Web Site >> PUBLIC >>Properties >> Directory Security tab >> Secure Communications >> Edit button

Secure Channel and 128 bit Encryption should be selected. Under "Client Certificates", the "ignore client certificates" option should be selected. All other checkboxes should be cleared.

Criteria: If "Secure Channel" and "128 bit Encryption" are selected, with "ignore client certificates", this is not a finding.

Fix Text (F-19440r1_fix)
Set Public Folders Web Security. Procedure: IIS Manager>> [Server name]>>Web Sites>>Default Web Site >> PUBLIC >>Properties >> Directory Security tab >> Secure Communications >> Edit button Select "Secure Channel" and "128 bit encryption". Under Client Certificates, select the “ignore client certificates” option. All other check boxes should be cleared.