The present paper proposes a new method for hiding any encrypted secret message inside a text/ASCII or Microsoft word document file, by manipulating the blank/white space characters of a cover file. Initially the secret message is encrypted using Modified Generalized Vernam Cipher Method (MGVCM) proposed by Nath et. al. For hiding secret message inside any ASCII file we propose a new method in which the bits of each character of secret message file is inserted in place of eight randomly selected blank space characters of the cover file. For inserting bit-0 we choose one blank space inside the cover file and to embed bit-1 we convert the blank space to ASCII code 160 and this is will show as blank in the screen and while printing in paper also. To embed bit-0 and bit-1 in cover file we select the blank spaces from cover file in random manner. The randomly selected blank characters are read from cover file correspond to positions of a shuffled offset matrix starting from a certain base address in cover file. The offset matrix is randomized using the randomization method of the previously published MSA encryption algorithm. The randomized embedding of message in a cover file gives an additional layer of security over the encryption.

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