Re: Netcat through Proxy

From: Rod S (securitybasics_at_gmail.com)
Date: 04/14/05

  • Next message: Nicholas Timperio: "RE: Blackberry Security concerns"
    Date: Thu, 14 Apr 2005 08:18:32 -0400
    To: security-basics@securityfocus.com
    
    

    So, it is possible to tunnel a netcat connection through a squid http
    proxy server?

    On 4/13/05, adisegna@siscocorp.com <adisegna@siscocorp.com> wrote:
    > The pix won't provide the level of application layer filtering you would
    > need to prevent this. I also use a PIX and have to deal with the same
    > issue. The PIX is great for speed and preventing outside attacks but not
    > inside out attacks (internal users) from open ports like http (80). I am
    > now in the process testing an application layer firewall to stick behind
    > the PIX to combat this problem. This will be a growing concern for
    > corporations using level 3 and 4 type firewall appliances.
    >
    > AD
    > Information Technology Group
    > Security Identification Systems Corporation
    >
    >
    > -----Original Message-----
    > From: Rod S [mailto:securitybasics@gmail.com]
    > Sent: Wednesday, April 13, 2005 12:00 PM
    > To: security-basics@securityfocus.com
    > Subject: Netcat through Proxy
    >
    > Hello,
    >
    > I have a squid proxy server running, caching and filtering web access.
    > User workstations on my network are only allowed http access through
    > this proxy server. The firewall (Cisco PIX) will not let them connect
    > outbound to any ports.
    >
    > I've done some testing and was successful in running netcat to connect
    > to a remote server listening with netcat on port 80 and get a command
    > prompt for an internal machine (which is allowed to connect to any
    > outgoing ports) on that remote server. I'm wondering if it's possible
    > for netcat to connect through our proxy server to a remote machine and
    > send a cmd.exe shell in the same way? Any tips on preventing this or
    > any other information you care to share is appreciated.
    >
    > Thanks!
    > Rod
    >
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    >

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  • Next message: Nicholas Timperio: "RE: Blackberry Security concerns"

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