RE: [PEN-TEST] Detecting the presence of a firewall

From: Geoghegan, Glyn (ISS London) (glyngat_private)
Date: Mon May 14 2001 - 13:53:00 PDT

  • Next message: railwayclubposseat_private: "Re: [PEN-TEST] Download fw1 topology"

    nmap scans of poorly configured FW-1 boxes may also show UDP/53 and TCP/53
    as 'closed' on the firewall and protected hosts, due to DNS lookups being
    permitted in the 'Policy Properties' dialogues.
    
    Whilst this is a relatively old mis-configuration (dates to early 4.0
    deployments), it's still fairly common, and provides opportunities for an
    attacker to probe hosts behind the firewall, or to abuse those hosts through
    trojans or tunnelling.
    
    http://www.phoneboy.com/faq/0131.html
    
    G
    
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    -----Original Message-----
    From: railwayclubposseat_private
    [mailto:railwayclubposseat_private]
    Sent: 14 May 2001 17:44
    To: PEN-TESTat_private
    Subject: RE: [PEN-TEST] Detecting the presence of a firewall
    
    
    For Checkpoint, use nmap and do a TCP and OS detection scan. If they are 
    doing one-to-many NAT the machines will be detected as "behind a Checkpoint 
    Firewall-1 4.1 SP2 Server" or whatever. The firewall itself is likely to 
    have some combination of  TCP ports 256-259, 264-265 open for management,
    auth, key exchange, etc. 
    
    >-----Original Message-----
    >From: priya subramanian [mailto:pentestingat_private]
    >Sent: Monday, May 07, 2001 5:11 AM
    >To: PEN-TESTat_private
    >Subject: [PEN-TEST] Detecting the presence of a firewall
    >
    >
    >Pl clarify the following
    >
    >1. Are there any means of detecting the presence of a
    >checkpoint firewall at a company's premises,  from a
    >remote location.
    >
    >2.Knowing one interface of the firewall machine, is it
    >possible for me to find the ip addresses of the other
    >interfaces.
    >
    >Kindly reply at the earliest.
    >
    >Priya
    >
    >Free, encrypted, secure Web-based email at www.hushmail.com
    >
    Free, encrypted, secure Web-based email at www.hushmail.com
    



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