3 ms·
According to [the Shattered paper](http://shattered.io/static/shattered.pdf http://shattered.io/static/shattered.pdf), the reason why the proof-of-concepts are
by lxe 10y ago
According to [the Shattered paper](http://shattered.io/static/shattered.pdf http://shattered.io/static/shattered.pdf), the reason why the proof-of-concepts are PDFs is because we are looking at a
> identical-prefix collision attack, where a given prefix P is extended with
two distinct near-collision block pairs such that they collide for any suffix S
They have already precomputed the prefix (the PDF header) and the blocks (which I'm guessing is the part that tells the PDF reader to show one image or the other), and all you have to do is to populate the rest of the suffix with identical data (both images)
- danielweber 10y agoYep. With any hash function that takes input as blocks, if you were to ever get two messages to generate the same EDIT internal state, you could add the same arbitrary data to both and get those new messages to have the same hash.