A website administrator has received an alert from an application designed to check the integrity of the company's website. The alert indicated that the hash value for a particular MPEG file has…

Cryptography is a broad field encompassing secure communication, including encryption and hashing, but doesn't specifically describe the method of altering a file's hash while maintaining its perceived content.

Time of check/time of use (TOCTOU) describes a race condition vulnerability, which is unrelated to hidden data within a file altering its hash.

Man in the middle (MITM) describes an attack where an attacker intercepts communication, not the specific method of embedding data invisibly within a file's content.

Covert timing channels are methods of transmitting information by manipulating the timing of system events or processes, which is not applicable to a file's content and hash changing.

Steganography is the practice of concealing a file, message, image, or video within another file, making the changes imperceptible to human senses but altering the underlying binary data. This alteration would cause the file's hash value to change, even if the visible media appears identical.