A secure authentication image file is generated for use in authenticating a device. The device performs a secure authentication algorithm on the secure authentication image file and a received plaintext challenge, and outputs a cyphertext response. If the cyphertext response matches a pre-stored cyphertext string associated with the plaintext challenge, then the device is authenticated. The secure authentication image file is pre-generated in a secure environment. A plurality of key address locations are reserved in a raw memory image file. A key merger application merges the secure key data into the raw memory image file to generate a secure authentication image file. A test set of plaintext/cyphertext pairs are generated using the newly created secure authentication image file. To maintain security of the secure authentication image file, the secure key data and the raw memory image file are erased from a working memory. The test set of plaintext/cyphertext pairs are used to verify a production device containing the secure authentication image file.