Please update libssh 0.5.3 as soon as possible in all supported Fedora versions!!!
libssh-0.5.3-1.fc18 has been submitted as an update for Fedora 18.
*** This bug has been marked as a duplicate of bug 878521 ***
libssh-0.5.3-1.fc18 has been pushed to the Fedora 18 stable repository. If problems still persist, please make note of it in this bug report.