A Vulnerability Assessment of “Indelible” Voter’s Ink
Many countries use supposedly “indelible” ink to stain a voter’s finger to prevent multiple votes by the same person. This ink is usually composed of silver nitrate, and is sometimes also used when countries replace their currency. In this study, I devise and demonstrate 6 different low-cost methods for preventing and/or removing silver nitrate stains. Though not fully optimized, all of these methods worked fairly well, and can probably be used in practice for duplicate voting multiple times per day per voter. The attacks might also work for the less common uv-fluorescent voter inks.
I also propose countermeasures for detecting these kinds of attacks, but it is questionable if they are adequate to detect voter fraud.
This work is only preliminary and has serious limitations.