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Hack or bug?

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bcrown
Posts: 4
Joined: 2016-08-31 14:21

Hack or bug?

Post by bcrown »

I am using uvnc server version 1.2.1.1

Occasionally I have been getting pop ups stating:

Remote Connection
could not connect
followed by an ip address which changes

My setup is configured to display a query window upon an incoming connection but this window does not pop up. It does pop up when i connect via normal channels.

Is this message a sign of some form of back door attempt or something else?

thanks for any advice and information
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Rudi De Vos
Admin & Developer
Admin & Developer
Posts: 6838
Joined: 2004-04-23 10:21
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Re: Hack or bug?

Post by Rudi De Vos »

That's a connection from a non "rfb protocol" device, Like a port scanner.
Vnc disconnect all non rfb connections, but give this popup.
This is before we check if the ip is allow a connection ( query popup or blacklisted ip)

The popup is only needed when vnc make an outgoing connection and fail.
In that case the rfb fail indicate a bad connection.

For incoming connections, vnc just need to ignore non rfb connections... yes it's a bug.
But still, it indicate that that ip address scan the vnc port on your pc.

Will be disabled in next update

Current Order
1) non rfb -> disconnect -> balloon indication
2) blacklist-> disconnect
3) check if query popup is required --> show popup
bcrown
Posts: 4
Joined: 2016-08-31 14:21

Re: Hack or bug?

Post by bcrown »

Thanks Rudi,

This event caused me to take a furthe look at the logs. I noticed areference that looked like:

Wed Aug 31 09:08:58 2016
vncproperties.cpp : enddialog (OK)
--This security ID may not be assigned as the owner of this object.
vncproperties.cpp : dialog result = 1
c:\users\rudi\desktop\ultravnc_1211\winvnc\winvnc\vncpasswd.h : PASSWD : ToText called

I was wondering who rudi was, can I assume it was you and hardcoded somewhere in the compilation.
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Rudi De Vos
Admin & Developer
Admin & Developer
Posts: 6838
Joined: 2004-04-23 10:21
Contact:

Re: Hack or bug?

Post by Rudi De Vos »

c:\users\rudi\desktop\ultravnc_1211\winvnc\winvnc\vncpasswd.h
Is the path of a sourcefile, and yep it's on my desktop.

We generate a debug file during compilation, this allow us to analyse a crash dump.
Looks like the compiler add the actual path to find the debug lib.
Tki2001
8
8
Posts: 22
Joined: 2016-04-24 11:44

Re: Hack or bug?

Post by Tki2001 »

It may be a bit offtopic, but I get this ballon too on server, when the network connection is lost in the middle of a connection attempt from the viewer.
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