FreeBSD -- OpenSSH Remote Denial of Service vulnerability

Problem Description:
When processing the SSH_MSG_KEXINIT message, the server
could allocate up to a few hundreds of megabytes of memory
per each connection, before any authentication take place.
Impact:
A remote attacker may be able to cause a SSH server to
allocate an excessive amount of memory. Note that the default
MaxStartups setting on FreeBSD will limit the effectiveness
of this attack.