A method for verifying a target computer file with respect to a reference computer file, including defining a first area delimiting a portion of a reference file, and a second area delimiting a portion of a target file, the second area exhibiting the same size as the first area and being situated, inside the target file, at the same relative position with respect to the origin of this target file as the first area with respect to the origin of the reference file; calculating a first digital imprint, by applying a hash function solely to that portion of the reference file which is contained inside the first area to be tested; calculating a second digital imprint, by applying the same hash function solely to that portion of the target file which is contained inside the second area to be tested; comparing the first and second digital imprints.