Confidentiality of controlled information during transmission through the use of an approved TLS version.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-213967	SQL6-D0-008300	SV-213967r754612_rule		Medium

Description

Transport Layer Security (TLS) encryption is a required security setting as a number of known vulnerabilities have been reported against Secure Sockets Layer (SSL) and earlier versions of TLS. 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. SQL Server must use a minimum of FIPS 140-2-approved TLS version 1.2, and all non-FIPS-approved SSL and TLS versions must be disabled. NIST SP 800-52 Rev.2 specifies the preferred configurations for government systems. References: TLS Support 1.2 for SQL Server: https://support.microsoft.com/en-us/kb/3135244 TLS Registry Settings: https://docs.microsoft.com/en-us/windows-server/security/tls/tls-registry-settings

STIG	Date
MS SQL Server 2016 Instance Security Technical Implementation Guide	2021-06-14

Details

Check Text ( C-15184r313684_chk )

Access the SQL Server Access an administrator command prompt Type "regedit" to launch the Registry Editor Navigate to: HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2 If this key does not exist, this is a Finding. Verify a REG_DWORD value of "0" for "DisabledByDefault" and a value of "1" for "Enabled" for both Client and Server. Navigate to: HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0 HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1 HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0 HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0 Under each key, verify a REG_DWORD value of "1" for "DisabledByDefault" and a value of "0" for "Enabled" for both Client and Server subkeys If any of the respective registry paths are non-existent or contain values other than specified above, this is a finding. If Vendor documentation supporting the configuration is provided, reduce this finding to a CAT 3.

Fix Text (F-15182r313685_fix)

Important Note: Incorrectly modifying the Windows Registry can result in serious system errors. Before making any modifications, ensure you have a recent backup of the system and registry settings. Access the SQL Server Access an administrator command prompt Type "regedit" to launch the Registry Editor Enable TLS 1.2: 1.Navigate to the path HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols a.If the "TLS 1.2" key does not exist, right-click "Protocols" b.Click New c.Click Key d.Type the name "TLS 1.2" 2.Navigate to the "TLS 1.2" subkey a.If the subkey "Client" does not exist, right-click "TLS 1.2" b.Click New c.Click Key d.Type the name "Client" e.Repeat steps A – D for the "Server" subkey 3.Navigate to the "Client" subkey a.If the value "Enabled" does not exist, right-click on "Client" b.Click New c.Click DWORD d.Enter "Enabled" as the name e.Repeat steps A-D for the value "DisabledByDefault" 4.Double-click "Enabled" 5.In Value Data, enter "1" 6.Click OK 7.Double-click "DisabledByDefault" 8.In Value Data, enter "0" 9.Click OK 10.Repeat steps 3 – 9 for the "Server" subkey Disable unwanted SSL/TLS protocol versions: 1.Navigate to the path HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols a.If the "TLS 1.0" key does not exist, right-click "Protocols" b.Click New c.Click Key d.Type the name "TLS 1.0" 2.Navigate to the "TLS 1.0" subkey a.If the subkey "Client" does not exist, right-click "TLS 1.0" b.Click New c.Click Key d.Type the name "Client" e.Repeat steps A – D for the "Server" subkey 3.Navigate to the "Client" subkey a.If the value "Enabled" does not exist, right-click on "Client" b.Click New c.Click DWORD d.Enter "Enabled" as the name e.Repeat steps A-D for the value "DisabledByDefault" 4.Double-click "Enabled" 5.In Value Data, enter "0" 6.Click OK 7.Double-click "DisabledByDefault" 8.In Value Data, enter "1" 9.Click OK 10.Repeat steps 3 – 9 for the "Server" subkey 11.Repeat steps 1 – 10 for "TLS 1.1", "SSL 2.0", and "SSL 3.0"