KTH Kth Kerberos 4

The Kerberos Telnet protocol, as implemented by KTH Kerberos IV and Kerberos V (Heimdal), does not encrypt authentication and encryption options sent from the server, which allows remote attackers to downgrade authentication and encryption mechanisms via a man-in-the-middle attack.

Buffer overflow in the kdc_reply_cipher function in KTH Kerberos IV allows remote attackers to cause a denial of service and possibly execute arbitrary commands via a long authentication request.

KTH Kerberos IV allows local users to change the configuration of a Kerberos server running at an elevated privilege by specifying an alternate directory using with the KRBCONFDIR environmental variable, which allows the user to gain additional privileges.

Kerberos 4 allows remote attackers to obtain sensitive information via a malformed UDP packet that generates an error string that inadvertently includes the realm name and the last user.

KTH Kerberos IV and Kerberos V (Heimdal) for Telnet clients do not encrypt connections if the server does not support the requested encryption, which allows remote attackers to read communications via a man-in-the-middle attack.

KTH Kerberos IV allows local users to overwrite arbitrary files via a symlink attack on a ticket file.