The rfbProcessClientNormalMessage function in libvncserver/rfbserver.c in LibVNCServer 0.9.9 and earlier allows remote attackers to cause a denial of service (divide-by-zero error and server crash) via a zero value in the scaling factor in a (1) PalmVNCSetScaleFactor or (2) SetScale message.
Exploitability
AV:NAC:MAu:NImpact
C:NI:NA:P4.3/AV:N/AC:M/Au:N/C:N/I:N/A:P