Title

The encryption type for password protected Office 97 thru Office 2003 must be set. (Cat II impact)

Discussion

This policy setting enables you to specify an encryption type for password-protected Office 97-2003 files. If you enable this policy setting, you can specify the type of encryption that Office applications will use to encrypt password-protected files in the older Office 97-2003 file formats. The chosen encryption type must have a corresponding cryptographic service provider (CSP) installed on the computer that encrypts the file. See the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\Defaults\Provider\ registry key for a list of CSPs installed on the local computer. Specify the encryption type to use by entering it in the provided text box in the following form:<Encryption Provider>,<Encryption Algorithm>,<Encryption Key Length>.For example, Microsoft Enhanced Cryptographic Provider v1.0,RC4,128. If you do not configure this policy setting, Excel, PowerPoint, and Word use Office 97/2000 Compatible encryption, a proprietary encryption method, to encrypt password-protected Office 97-2003 files.

Check Content

Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Office 2016 -> Security Settings "Encryption type for password protected Office 97-2003 files" is set to "Enabled (Microsoft Enhanced RSA and AES Cryptographic Provider,AES 256,256)". Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\16.0\common\security Criteria: If the value DefaultEncryption12 is REG_SZ = "Microsoft Enhanced RSA and AES Cryptographic Provider,AES 256,256", this is not a finding.

Fix Text

Set the policy value for User Configuration -> Administrative Templates -> Microsoft Office 2016 -> Security Settings "Encryption type for password protected Office 97-2003 files" to "Enabled (Microsoft Enhanced RSA and AES Cryptographic Provider,AES 256,256)".

Additional Identifiers

Rule ID: SV-238029r879642_rule

Vulnerability ID: V-238029

Group Title: SRG-APP-000231

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.