Quote:Recently, a NSA document detailing a Russian plan to hack US voting machines became public. A source in the NSA apparently shared the documents with online publication The Intercept, which scanned and printed these documents. Barely a few hours later, a defence intelligence contractor named Reality Winner was arrested for sharing classified information, having been unintentionally outed by the journalists she’d shared the document with. It was later revealed that the NSA traced the leak to Winner thanks to The Intercept’s report publishing digital scans of the documents she’d printed and shared.

Wait, what? A scan of a printout was traced back to an individual, how? Does the NSA use some special kind of printer that can be used to trace prints back to an individual? The answer is no, and the fact is this ‘tracing technology’ is present in everyday printers that is used by you at home and office.

Sounds crazy, right? It turns out that this is something pretty well known - just not to the general public. It turns out that almost all colour laser printers print a special pattern of "microdots" - a tiny grid of dots small and faint enough that you can't see them with the naked eye under normal lighting.

https://gadgets.ndtv.com/laptops/features/nsa-leaker-reality-winner-microdots-printer-spying-metadata-1714577