Improper authentication vulnerability in GOT2000 series GT27 model VNC server versions 01.39.010 and prior, GOT2000 series GT25 model VNC server versions 01.39.010 and prior, GOT2000 series GT21 model GT2107-WTBD VNC server versions 01.40.000 and prior, GOT2000 series GT21 model GT2107-WTSD VNC server versions 01.40.000 and prior, GOT SIMPLE series GS21 model GS2110-WTBD-N VNC server versions 01.40.000 and prior and GOT SIMPLE series GS21 model GS2107-WTBD-N VNC server versions 01.40.000 and prior allows a remote unauthenticated attacker to gain unauthorized access via specially crafted packets when the "VNC server" function is used.