The website “theintercept.com” released documents on election tampering from an NSA leaker. “Reality Winner”, an NSA contractor, was arrested soon thereafter an arrest warrant had been issued and was published online. The documents she printed contained tiny yellow Microdots, and the warrant showed how the NSA tracked her down via the documents she sent to the Intercept. The published Intercept document was not the original scanned PDF file but a PDF containing pictures of the printed document.
Several decades ago when the advent of the color printer came about, and the technology approached near photo perfect, the Treasury Department realized they had a major problem. Color copiers could copy currency and create counterfeit notes.…show more content… Click on Select and then All or Ctrl + A to select the whole document.
Imported GIMP Document.
Now Select Colors and then Invert, the document will appear as below.
GIMP Document with Inverted Colors.
Zoom in to any white space or in this case dark space. Enlarging the image below you will see what appears to be groups of blue (the inverse of yellow) dots arranged in a rectangular pattern.
GIMP Document - Zoom In
All That Is Hidden Can Now Be Seen
Select one of these patterns and make sure you have a 15 wide by 8 dot tall block.
GIMP Document - Microdots
If we go to the Electronic Frontier Foundation (EFF) – DocuColor Tracking Dot Decoding Guide WEB page we immediately notice that column one, row one does not have a dot in it and we must rotate the image 180 degrees to properly orient the pattern for decoding. In GIMP, under the Image tab, select Transform, and Rotate 180 degrees. Once done we can use the EFF page to decode the dots.
GIMP Document - Rotated 180
Now we can match the dot pattern to the import form for decoding.
EFF Microdot Pattern
After matching the dot to its corresponding row and column we can fill in the code above, click on the Submit button to return the results.
EFF Microdot Pattern Decoded
The document leaked by the Intercept was from a printer with model number 54 and the serial number 29535218. We can see that on May 9, 2017, at 6:20, the document was printed. The NSA knows which