WG340 IIS7 - A private web server must utilize an approved TLS version.

Information

Transport Layer Security (TLS) encryption is a required security setting for a private web server. Encryption of private information is essential to ensuring data confidentiality. If private information is not encrypted, it can be intercepted and easily read by an unauthorized party. A private web server must use a FIPS 140-2 approved TLS version, and all non-FIPS-approved SSL versions must be disabled.

Solution

1. Open the IIS Manager.
2. Click the site name under review.
3. Double click the SSL Settings Icon.
4. Click the Require SSL and Require SSL 128-Bit check boxes.

Note: If the Required SSL 128-Bit setting is not visible, the setting can be set by clicking the site node and then opening the Configuration Editor. Switch to the section, the dropdown at the top of the configuration editor, system.webServer/security/access. Click the value beside the sslFlags and select ssl128 in the dropdown list.

5. Set the version of SSL/TLS by creating and setting the following registry to not allow anything lower than TLS. Ensure the following value exists in each of the keys:

Enabled REG_DWORD 0

HKey_Local_Machine\System\CurrentControlSet\Control\SecurityProviders \SCHANNEL\Protocols\PCT 1.0\Client

HKey_Local_Machine\System\CurrentControlSet\Control\SecurityProviders \SCHANNEL\Protocols\PCT 1.0\Server

HKey_Local_Machine\System\CurrentControlSet\Control\SecurityProviders \SCHANNEL\Protocols\SSL 2.0\Client

HKey_Local_Machine\System\CurrentControlSet\Control\SecurityProviders \SCHANNEL\Protocols\SSL 2.0\Server

HKey_Local_Machine\System\CurrentControlSet\Control\SecurityProviders \SCHANNEL\Protocols\SSL 3.0\Client

HKey_Local_Machine\System\CurrentControlSet\Control\SecurityProviders \SCHANNEL\Protocols\SSL 3.0\Server

The keys for TLS 1.0 do not require the Enabled value to be present, but if it is, it needs to be set to REG_DWORD 1, to enable TLS.

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_MS_IIS_7-0_STIG.zip

Item Details

Category: CONFIGURATION MANAGEMENT, SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|CM-7, 800-53|SC-8(1), 800-53|SC-13, CAT|II, CSCv6|9.1, Rule-ID|SV-32334r5_rule, STIG-ID|WG340_IIS7, Vuln-ID|V-2262

Plugin: Windows

Control ID: d338d361629246199e79d73b6bf4623e6c4095378cddeaa5dcb45204bba7463d