Title

Internet Explorer Processes for MK protocol is not enabled. (Explorer) (Cat II impact)

Discussion

The MK Protocol Security Restriction policy setting reduces attack surface area by blocking the seldom used MK protocol. Some older Web applications use the MK protocol to retrieve information from compressed files. Setting this policy to Enabled blocks the MK protocol for Windows Explorer and Internet Explorer, which causes resources that use the MK protocol to fail. Disabling this setting allows applications to use the MK protocol API. Because the MK protocol is not widely used, it should be blocked wherever it is not needed. This appendix recommends you configure this setting to Enabled to block the MK protocol unless you specifically need it in your environment. Note: Because resources that use the MK protocol will fail when you deploy this setting, you should ensure that none of your applications use the MK protocol.

Check Content

The policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Internet Explorer -> Security Features -> MK Protocol Security Restriction -> "Internet Explorer Processes" will be set to “Enabled”. Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Internet Explorer\Main\FeatureControl\FEATURE_DISABLE_MK_PROTOCOL Criteria: If the value explorer.exe is REG_SZ = 1, this is not a finding

Fix Text

The policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Internet Explorer -> Security Features -> MK Protocol Security Restriction -> "Internet Explorer Processes" will be set to “Enabled”. Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Internet Explorer\Main\FeatureControl\FEATURE_DISABLE_MK_PROTOCOL Criteria: Set the value explorer.exe to REG_SZ = 1.

Additional Identifiers

Rule ID: SV-16397r1_rule

Vulnerability ID: V-15550

Group Title:

Expert Comments

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