The kadm5_modify_policy_internal function in lib/kadm5/srv/svr_policy.c in the Kerberos administration daemon (kadmind) in MIT Kerberos 5 (krb5) 1.5 through 1.6.2 does not properly check return values when the policy does not exist, which might allow remote authenticated users with the "modify policy" privilege to execute arbitrary code via unspecified vectors that trigger a write to an uninitialized pointer.