VOGONS


First post, by Anonymous coward

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I just got a message from ZoneAlarm telling me that Dosbox was trying to act as a telnet server. Why is this?

Thanks

Anonymous

Reply 1 of 9, by Magamo

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By default, DosBox 0.61 binds to port 23 (the Telnet port) for its modem emulation.

Reply 2 of 9, by Anonymous coward

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Is there a way to turn that off at all?

Thanks

Reply 3 of 9, by mirekluza

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Yes, see DOSBOX.CONF. Switch off modem emulation.

Mirek

Reply 5 of 9, by SymeRegdButNoReplyYet

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[I've just installed and run DOSBox v0.61 for the first time and was somewhat surprised and concerned that it caused my firewall to give a warning that it was trying to access the Internet. Presumably this is due to the virtual tcp/ip modem code, and because the default DOSBOX.CONF file contains the settings "modem=true", "comport=2" and "listenport=23"?] To avoid causing users unnecessary concern, and to avoid opening or accessing ports unnecessarily (and possibly compromising users' security), would it not be better to set the virtual modem code as off (modem=false) by default? Anyone competent enough to want to use the modem feature should be competent enough to turn it on in the config.
Apart from that, thanks for a great piece of software.

Reply 7 of 9, by priestlyboy

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Yep, I could switch it to off in the settings before I make the next DB build.

Ieremiou
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Helping Debug DOSBox.

Reply 8 of 9, by canadacow

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I highly doubt that opening the telnet port automatically within DosBox presents any security vunerability because:

1. Not enough people use DosBox. It wouldn't be a very reliable service to hack.

2. Anyone connecting to the port effectively sees the techincal end of a RS232 port. Nothing to see here... move on.

3. DosBox is an emulator, so, if by the really weird possibility someone was able to run something remotely inside DosBox (really, really unlikely), just close DosBox.

Reply 9 of 9, by Qbix

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I'll turn it off though (as with all optional modules) as people who do not have sdl_net installed will have the same primary configfile as the people who don't.

I don't think it's used that much and people like to use should at least be capable of turning it on 😀

Water flows down the stream
How to ask questions the smart way!