Heimdal is a free implementation of Kerberos 5.
The ftpd and rcp applications provided by Heimdal fail to check the return value of calls to seteuid().
A local attacker could exploit this vulnerability to execute arbitrary code with elevated privileges.
There is no known workaround at this time.
All Heimdal users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-crypt/heimdal-0.7.2-r3"