Tim Dierks wrote:
- Get browser makers to design better ways to communicate to users that UI elements can be trusted. For example, a proposal I saw recently which would have the OS decorate the borders of "trusted" windows with facts or images that an attacker wouldn't be able to predict: the name of your dog, or whatever. (Sorry, can't locate a link right now, but I'd appreciate one.)
It was none other than Microsoft's NGSCB, nee Palladium. See http://news.com.com/2100-1012_3-1000584.html?tag=fd_top: NEW ORLEANS--Microsoft is trying to make security obvious. The software giant plans to visually alter document or application windows that contain private information that's secured through Microsoft's Next-Generation Secure Computing Base (NGSCB), formerly known as Palladium. Secure windows will look different than regular, unsecured windows in order to remind users that they are looking at confidential material, Peter Biddle, product unit manager for Microsoft, said Thursday at the Windows Hardware Engineering Conference (WinHEC) here. ... The border of a secured page may contain information--such as the names of all the dogs that someone has ever owned--to make the data instantly recognizable as sound to the individual owner, as well as difficult to replicate. A hacker can create a spoof page with dogs' names running along the border but, in all likelihood, not one reading "Buffy, Skip and Jack Daniels--and in that order," Biddle said. ... Information on secured windows will vanish if another window is placed on top of it or shifted to the background. Erasing the information will prevent certain types of attacks and remind people that they're dealing with confidential material, Biddle said. When the secure window returns to the top of the stack, the information will reappear, he said. I don't see how this is going to work. The concept seems to assume that there is a distinction between "trusted" and "untrusted" programs. But in the NGSCB architecture, Nexus Computing Agents (NCAs) can be written by anyone. If you've loaded a Trojan application onto your machine, it can create an NCA, which would presumably be eligible to put up a "trusted" window. So either you have to configure a different list of doggie names for every NCA (one for your banking program, one for Media Player, one for each online game you play, etc.), or else each NCA gets access to your Secret Master List of Doggie Names. The first possibility is unmanageable and the second means that the trustedness of the window is meaningless. So what good is this? What problem does it solve? --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majordomo@metzdowd.com