The (1) ftpd and (2) ksu programs in (a) MIT Kerberos 5 (krb5) up to 1.5, and 1.4.x before 1.4.4, and (b) Heimdal 0.7.2 and earlier, do not check return codes for setuid calls, which might allow local users to gain privileges by causing setuid to fail to drop privileges.  NOTE: as of 20060808, it is not known whether an exploitable attack scenario exists for these issues.