Heimdal 0.6.x before 0.6.1 and 0.5.x before 0.5.3 does not properly perform certain consistency checks for cross-realm requests, which allows remote attackers with control of a realm to impersonate others in the cross-realm trust path.

Multiple buffer overflows in Heimdal before 0.5, possibly in both the (1) kadmind and (2) kdc servers, may allow remote attackers to gain root access.

Unknown vulnerabilities in Heimdal before 0.5 with unknown impact, possibly in the (1) kadmind and (2) kdc servers, may allow remote or local attackers to gain root or other access, but not via buffer overflows (CVE-2002-1225).