A National Security Agency (NSA) contractor was caught after leaking classified documents.
Life Hacker reported that 25 year old Reality Leigh Winner leaked the classified documents from the NSA to The Intercept for which she was arrested. The documents leaked were allegedly about detailed Russian cyberattacks in a report from the NSA.
Winner was one of six who printed the report but she was the only individual who had contact with The Intercept via e-mail and the warrant for her arrest from the Justice Department stated that the “classified information was tracked to Winner”. The tracking was via the publication she published which was used to identify her.
Unbeknown to many modern printers have technology called printer steganography which is “the practice of hiding data” inside other data and uses “dots or lines printed throughout the document that correspond to a certain pattern” and from this the date, time of printing and the printer used can be identified and according to the article Electronic Frontier Foundation said that steganography dots are a feature of colour laser printers and copiers but not inkjet nor black and whitelaser.
After an internal investigation by the US Government Agency six people were found to have printed the report but she was the only one with an email contact for The Intercept. The printer Winner used was a Xerox DocuColor and the NSA would have been able to track Winner from the hidden data which showed the time of printing after which all they had to do was find out who was printing at that time.