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#151929 23/06/06 07:26 PM
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pmak Offline OP
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If I DCC SEND a file to someone, then while mIRC is waiting for that person to accept the file, anyone who connects to the TCP port that my mIRC is listening on to send the file (even if it's not the intended recipient) will receive the file!

This has very bad security implications for sending private files.

Is there any solution, or should I not use DCC SEND to send private files?

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Hoopy frood
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depends on what you mean by "private files" are we talking about making a credit card purchase via mIRC? sending "hot pictures"?

I would say you have to balance the risk against the nature of what you are sending.

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Hoopy frood
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Quote:
Is there any solution, or should I not use DCC SEND to send private files?


You should not use dcc send then. If this concerns you so.

I would really like to see statistics on how many times this has been achived by anyone covertly to "steal the file", you would have to attach to the port and match the dcc send protocol and download the file untill it didnt send anymore, you cant just attach a mirc to download it, as for that you would need to have forged a dcc send to the client and that means u already knew the length of the file. And u also have to time it up to get in during that what 1 to 1.5 second max window that the server is paused waiting for a connection on.


However I know its possable to do In a non covert way, I wrote a script to take advantage of just this "ability", It has a bot sitting in one channel offering a selection of files (errrr shareware smile ) that are actually on a private bot in another channel, when someone requests a file in channel 1, the bot requests the file in channel2, traps the inbound DCC SEND message to it from the channel 2 server and duplicates a similar message from itself but with the IP and port of the channel 2 server to the channel 1 requester, then ignores the DCC SEND, thus the channel 1 requester sees the DCC SEND from the bot and ataches to the port & IP of the channel 2 bot. The requester and sender are none the wiser, they both see the bots name as sender & reciever.
PS: The bot is ment to be doing this for anyone who wants to yell that this is sooo evil etc.

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pmak Offline OP
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Quote:
I would really like to see statistics on how many times this has been achived by anyone covertly to "steal the file", you would have to attach to the port and match the dcc send protocol and download the file untill it didnt send anymore, you cant just attach a mirc to download it, as for that you would need to have forged a dcc send to the client and that means u already knew the length of the file. And u also have to time it up to get in during that what 1 to 1.5 second max window that the server is paused waiting for a connection on.


Matching the protocol doesn't seem to be hard: If you just telnet to the port that the DCC SEND server is listening on, it'll send you all the data.

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Hoopy frood
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Yeah fine, IF you telnet to the right Ip on the right port at the right time then it just might. right?


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