The Internet Explorer SSL/TLS parameter must be set correctly.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-6238	DTBI014	SV-45415r2_rule	ECSC-1	Medium

Description
This parameter ensures only DoD-approved ciphers and algorithms are enabled for use by the web browser. TLS and SSL are protocols for protecting communications between the browser and the target server. When the browser attempts to set up a protected communication with the target server, the browser and server negotiate which protocol and version to use. The browser and server attempt to match each other's list of supported protocols and versions and pick the most preferred match.

Description

This parameter ensures only DoD-approved ciphers and algorithms are enabled for use by the web browser. TLS and SSL are protocols for protecting communications between the browser and the target server. When the browser attempts to set up a protected communication with the target server, the browser and server negotiate which protocol and version to use. The browser and server attempt to match each other's list of supported protocols and versions and pick the most preferred match.

STIG	Date
Microsoft Internet Explorer 10 Security Technical Implementation Guide	2013-09-30

Details

Check Text ( C-42764r2_chk )
Open Internet Explorer. From the menu bar select Tools. From the Tools drop-down menu, select Internet Options. From the Internet Options window, select the Advanced tab, from the Advanced tab window scroll down to the Security category, verify a check mark is placed in the "Use SSL 3.0" and "Use TLS 1.0" checkboxes. Verify there is not a check placed in the checkbox for SSL2.0. The policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Internet Explorer-> Internet Control Panel-> Advanced Page-> "Turn off Encryption Support" must be "Enabled" and select "Use SSL 3.0 and TLS 1.0" from the drop down in the Options window. Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings Criteria: If the value SecureProtocols is REG_DWORD = a0 (hex), this is not a finding. If the value SecureProtocols is REG_DWORD = a8 (hex), this is a finding.

Check Text ( C-42764r2_chk )

Open Internet Explorer. From the menu bar select Tools. From the Tools drop-down menu, select Internet Options. From the Internet Options window, select the Advanced tab, from the Advanced tab window scroll down to the Security category, verify a check mark is placed in the "Use SSL 3.0" and "Use TLS 1.0" checkboxes. Verify there is not a check placed in the checkbox for SSL2.0.

The policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Internet Explorer-> Internet Control Panel-> Advanced Page-> "Turn off Encryption Support" must be "Enabled" and select "Use SSL 3.0 and TLS 1.0" from the drop down in the Options window.

Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings

Criteria: If the value SecureProtocols is REG_DWORD = a0 (hex), this is not a finding. If the value SecureProtocols is REG_DWORD = a8 (hex), this is a finding.

Fix Text (F-38812r2_fix)
Check mark the options to enable "SSL3" and "TLS 1.0" in the Internet Explorer Options, Advanced page. Uncheck the box option for SSL2.0. Change registry key HKLM\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings so that value SecureProtocols is REG_DWORD a0 (hex).