Abstract: A Content Disarm and Reconstruction (CDR) method is disclosed including a computer receiving an input file having a file format configured with a structured storage. The computer disassembles the structured storage into at least one subfile. Each subfile is a stream subfile. For each subfile, the computer identifies an item in the stream subfile. The computer analyzes the item in the stream subfile for an unwanted behavior by determining an acceptability of the unwanted behavior, distinguishing a visibility of the item, and recognizing a necessity of the item. The computer, based on a result of the analyzing step, processes the item in the stream subfile resulting in a processed subfile. The computer assembles the processed subfiles into an output file having the same file format as the file format as the input file.