Check: O365-CO-000019
Microsoft Office 365 ProPlus STIG:
O365-CO-000019
(in versions v2 r12 through v1 r1)
Title
The MIME Sniffing safety feature must be enabled in all Office programs. (Cat II impact)
Discussion
Encryption is only as good as the encryption modules utilized. Unapproved cryptographic module algorithms cannot be verified and cannot be relied upon to provide confidentiality or integrity, and DoD data may be compromised due to weak algorithms. The use of TLS provides confidentiality of data in transit between the application server and client. FIPS 140-2 approved TLS versions include TLS V1.0 or greater. TLS must be enabled and non-FIPS-approved SSL versions must be disabled. NIST SP 800-52 specifies the preferred configurations for government systems.
Check Content
Verify the policy value for Computer Configuration >> Administrative Templates >> Microsoft Office 2016 (Machine) >> Security Settings >> IE Security >> Mime Sniffing Safety Feature is set to "Enabled" and the check box is selected for every installed Office program. Use the Windows Registry Editor to navigate to the following key: HKLM\software\microsoft\internet explorer\main\featurecontrol\feature_mime_sniffing If the value for all installed Office Programs is REG_DWORD = 1, this is not a finding.
Fix Text
Set the policy value for Computer Configuration >> Administrative Templates >> Microsoft Office 2016 (Machine) >> Security Settings >> IE Security >> Mime Sniffing Safety Feature to "Enabled" for all installed Office programs.
Additional Identifiers
Rule ID: SV-223301r879616_rule
Vulnerability ID: V-223301
Group Title: SRG-APP-000179
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-000803 |
The information system implements mechanisms for authentication to a cryptographic module that meet the requirements of applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance for such authentication. |
Controls
Number | Title |
---|---|
IA-7 |
Cryptographic Module Authentication |