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bug. old bug. but probably nobody reported it yet

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costinel
Posts: 4
Joined: 2006-02-28 14:17

bug. old bug. but probably nobody reported it yet

Post by costinel »

open ultravnc viewer (listen mode)
then scan yourself with nmap

http://fac.ce.vreau.eu.org/ultravncbug.jpg

[mod=494,1141488209]moved from Bug rel 1.0.0 to General help, reason, is not a bug[/mod]
Last edited by costinel on 2006-03-04 16:03, edited 1 time in total.
rmoller
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40
Posts: 93
Joined: 2004-08-20 09:32

Post by rmoller »

Working as designed :)

It is little known, that the VNCviewer can listen at port 5400 for flash purposes. To verify it, start a VNCviewer in listen mode. Then telnet to 127.0.0.1 5400. Whatever you type will appear flashing fullscreen on the viewer PC.

This is inherited from the very first implementation of VNC at Olivetti Research Lab. They had implemented a roaming freeseating, where everyone carried a radio badge of a kind. Whenever they approached a terminal, their current desktop would appear on it (through a winvnc -connect ip adr.). If you were in a room with many PC's you needed a way to identify the PC with your desktop. Hence the "Flasher" listening port at 5400.

Could be used for teasing :roll:
costinel
Posts: 4
Joined: 2006-02-28 14:17

Post by costinel »

looooooooooool
i did not know that. this is annoying, however, if someone wants to block you from working :(
i expected, though, that the listening socket to be closed or communication ignored when i choose 'toggle listen mode on/off' from the systray icon
costinel
Posts: 4
Joined: 2006-02-28 14:17

Post by costinel »

is it possible to add an option to make it not listen to 5400 for flash purposes? realvnc does not listen to 5400 by default ....
Last edited by costinel on 2006-03-01 13:10, edited 1 time in total.
redge
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1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Post by redge »

pgmoney made a solution for stop this function
pgmoney wrote:Here is the vnc viewer .exe with the -noflash switch and vc6 source.
(256k download)

http://www.advantig.com/files/vncviewer101a4.zip

Usual disclaimer: Use at your own risk, took 10 minutes to modify and has not had much testing...
source:
[topic=4486][/topic]
Last edited by redge on 2006-03-01 22:09, edited 1 time in total.
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
costinel
Posts: 4
Joined: 2006-02-28 14:17

Post by costinel »

thanks, but i tried accesing the indicated url and i get a 404.
also, googling for "vncviewer101a4.zip" or "vncviewer101a4" gets zero results :(
redge
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1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Post by redge »

UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
redge
1000
1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Re: bug. old bug. but probably nobody reported it yet

Post by redge »

would be happy to have back the function -noflash for vncviewer
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
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