block ssh tunnels - Networking

This is a discussion on block ssh tunnels - Networking ; Hello I've some proxy that is configure to accept only 80 and 443 destination ports. But either that user can find shell account on 80 or 443 port and tunnel through this proxy to all internet. Is it possible to ...

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Thread: block ssh tunnels

  1. block ssh tunnels

    Hello

    I've some proxy that is configure to accept only 80 and 443 destination
    ports. But either that user can find shell account on 80 or 443 port and
    tunnel through this proxy to all internet. Is it possible to prevent that
    kind of actions that user can work only with http[s] sites without
    tunnels?



    --
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    ( @ @ ) mailto:dimmur-(at)-z-pl
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  2. Re: block ssh tunnels

    On Aug 24, 5:54*am, DimmuR wrote:

    > I've some proxy that is configure to accept only 80 and 443 destination
    > ports. But either that user can find shell account on 80 or 443 port and
    > tunnel through this proxy to all internet. Is it possible to prevent that
    > kind of actions that user can work only with http[s] sites without
    > tunnels?


    This is a human problem, not a technical problem. Review the logs and
    appropriately punish those who break the rules.

    DS

  3. Re: block ssh tunnels

    DimmuR wrote:
    > Hello
    >
    > I've some proxy that is configure to accept only 80 and 443 destination
    > ports. But either that user can find shell account on 80 or 443 port and
    > tunnel through this proxy to all internet. Is it possible to prevent that
    > kind of actions that user can work only with http[s] sites without
    > tunnels?


    SSH tunneling can be blocked, but there are tunneling
    methods using HTTP as the low-level transport. Have a
    look at e.g. corkscrew (you can Google for it).

    As soon as you open *any* connection to the Internet,
    you also open a way to transport clandestine tunneling.

    Would you please care to tell why?

    --

    Tauno Voipio
    tauno voipio (at) iki fi


  4. Re: block ssh tunnels

    On Sun, 24 Aug 2008 12:54:05 +0000 (UTC), DimmuR wrote:
    >Hello


    >I've some proxy that is configure to accept only 80 and 443 destination
    >ports. But either that user can find shell account on 80 or 443 port and
    >tunnel through this proxy to all internet. Is it possible to prevent that
    >kind of actions that user can work only with http[s] sites without
    >tunnels?


    RTFM, specifically sshd.conf




  5. Re: block ssh tunnels

    On Sun, 24 Aug 2008 12:54:05 +0000, DimmuR wrote:
    > I've some proxy that is configure to accept only 80 and 443 destination
    > ports. But either that user can find shell account on 80 or 443 port and
    > tunnel through this proxy to all internet. Is it possible to prevent
    > that kind of actions that user can work only with http[s] sites without
    > tunnels?


    Deny all sites and only allow those sites you trust.

    Wkr,
    Sven Vermeulen

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