40-bit RC4 Encryption

40-bit RC4 encryption is performed on portions of Office binary documents. For more information about how to determine whether 40-bit RC4 encryption is being used and the placement of the password verifier, see [MS-XLS] and [MS-DOC]. The same mechanisms for generating the password verifier, deriving the encryption key, and encrypting data are used for all file formats supporting 40-bit RC4 encryption.