@misc{cryptoeprint:2012:117,
author = {Ran Canetti and Margarita Vald},
title = {Universally Composable Security With Local Adversaries},
howpublished = {Cryptology ePrint Archive, Report 2012/117},
year = {2012},
note = {\url{http://eprint.iacr.org/}},
}
You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.