xdr_krb5_tl_data() in lib/kadm5/kadm_rpc_xdr.c in MIT Kerberos 5 (aka krb5) does not free partially decoded data on failure, which allows remote authenticated users to cause a denial of service (memory leak in kadmind) via crafted RPC requests that trigger a decode failure.
Restrict network access to kadmind to trusted hosts, or disable it in favor of kadmin.local server-side command line tool for administration operations if possible.