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UltraVNC 1.0.2 Client (vncviewer.exe) Buffer Overflow

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UltraVNC 1.0.2 Client (vncviewer.exe) Buffer Overflow



This module exploits a buffer overflow in UltraVNC Viewer 1.0.2 Release. If a malicious server responds to a client connection indicating a minor protocol version of 14 or 16, a 32-bit integer is subsequently read from the TCP stream by the client and directly provided as the trusted size for further reading from the TCP stream into a 1024-byte character array on the stack.


  • noperand




Module Options

To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':

msf > use exploit/windows/vnc/ultravnc_viewer_bof
msf exploit(ultravnc_viewer_bof) > show targets
msf exploit(ultravnc_viewer_bof) > set TARGET < target-id >
msf exploit(ultravnc_viewer_bof) > show options
    ...show and set options...
msf exploit(ultravnc_viewer_bof) > exploit

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