heimdal -- Multiple vulnerabilities

A Project heimdal Security Advisory reports:

The telnet client program in Heimdal has buffer overflows
in the functions slc_add_reply() and env_opt_add(), which
may lead to remote code execution.

The telnetd server program in Heimdal has buffer overflows
in the function getterminaltype, which may lead to remote code
execution.

The rshd server in Heimdal has a privilege escalation bug
when storing forwarded credentials. The code allowes a user
to overwrite a file with its credential cache, and get ownership
of the file.