diff --git a/lib/krb5/get_cred.c b/lib/krb5/get_cred.c
index 29e66e1b1..12345a119 100644
--- a/lib/krb5/get_cred.c
+++ b/lib/krb5/get_cred.c
@@ -483,6 +483,7 @@ add_cred(krb5_context context, krb5_creds ***tgts, krb5_creds *tkt)
 	return ENOMEM;
     *tgts = tmp;
     ret = krb5_copy_creds(context, tkt, &tmp[i]);
+    tmp[i+1] = NULL;
     return ret;
 }