This was a forensics challenge. We get a zip file named ziper.zip. Trying to extract it, we are greeted with an error message. unzip zipper.zip Archive: zipper.zip warning: filename too long–truncating. : bad extra field length (central) So, there is something wrong with the filename length. Possibly in the central headers. A quick readup on how ZIP files are constructed from ForensicsWiki and Structure of PKZip File helped a lot in solving this particular challenge.