Stack-based buffer overflow in the ClientConnection::NegotiateProtocolVersion function in vncviewer/ClientConnection.cpp in vncviewer for UltraVNC 1.0.2 and 1.0.4 before 01252008, when in LISTENING mode or when using the DSM plugin, allows remote attackers to execute arbitrary code or cause a denial of service (crash) via a modified size value.

More... (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2008-0610)