Methods and apparatus for attacking a screening algorithm. The methods include
the steps of marking content to be downloaded, inserting at least one section of
legitimate content into the marked content, and subjecting the content to a screening
algorithm. The screening algorithm may include the steps of determining a number
of segments that are included within the content, selecting at least two segments
within the content, screening the two segments to determine whether the two segments
verify correctly through the screening algorithm, and downloading the content when
it is determined that the two segments verify correctly through the screening algorithm.
Once the content has been successfully downloaded, the integrity of the downloaded
content may be restored by removing the legitimate content that was previously
inserted into the downloaded content.