John Markoff reports:
In less than two months after a group of University of Washington computer researchers proposed a novel system for making electronic messages “disappear” after a certain period of time, a rival group of researchers based at the University of Texas at Austin, Princeton, and the University of Michigan, has claimed to have undermined the scheme.
[…]
The Vanish attackers have created a demonstration system they call “Unvanish” and they said they had undone the Vanish model for gradually eroding encryption keys by subverting the peer-to-peer file sharing system. Their insight was to use a single computer to masquerade as a large number of members of a file sharing network. That rogue machine would simply need to capture and store anything that looked like a Vanish key fragment. The researchers said that this was simple, as the Vanish fragments are identifiable because of their size. Later it would be possible to reconstruct a Vanish message by simply consulting the Unvanish archive.
Read more in The New York Times.