Buffer overflow in NetSupport Manager (NSM) Client 10.00 and 10.20, and NetSupport School Student (NSS) 9.00, allows remote NSM servers to cause a denial of service or possibly execute arbitrary code via crafted data in the configuration exchange phase of an initial connection setup.  NOTE: a vendor statement, which is too vague to be sure that it is for this particular issue, says that only a denial of service is possible.