kdc_process_for_user(kdc_realm_t *kdc_active_realm,
                     krb5_pa_data *pa_data,
                     krb5_keyblock *tgs_session,
                     krb5_pa_s4u_x509_user **s4u_x509_user,
                     const char **status)
{
    krb5_error_code             code;
    krb5_pa_for_user            *for_user;
    krb5_data                   req_data;

    req_data.length = pa_data->length;
    req_data.data = (char *)pa_data->contents;

    code = decode_krb5_pa_for_user(&req_data, &for_user);
    if (code) {
        *status = "DECODE_PA_FOR_USER";
        return code;
    }

    code = verify_for_user_checksum(kdc_context, tgs_session, for_user);
    if (code) {
        *status = "INVALID_S4U2SELF_CHECKSUM";
        krb5_free_pa_for_user(kdc_context, for_user);
        return code;
    }

    *s4u_x509_user = calloc(1, sizeof(krb5_pa_s4u_x509_user));
    if (*s4u_x509_user == NULL) {
        krb5_free_pa_for_user(kdc_context, for_user);
        return ENOMEM;
    }

    (*s4u_x509_user)->user_id.user = for_user->user;
    for_user->user = NULL;
    krb5_free_pa_for_user(kdc_context, for_user);

    return 0;
}
The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.