NetSupport Manager (NSM) before 11.00.0005 sends HTTP headers with cleartext fields containing details about client machines, which allows remote attackers to obtain potentially sensitive information by sniffing the network.

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.

NetSupport Manager Client before 10.20.0004 allows remote attackers to bypass the (1) basic and (2) authentication schemes by spoofing the NetSupport Manager.