@misc{cryptoeprint:2006:265,
author = {Javier Herranz and Dennis Hofheinz and Eike Kiltz},
title = {Some (in)sufficient conditions for secure hybrid encryption.},
howpublished = {Cryptology ePrint Archive, Report 2006/265},
year = {2006},
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.