Security Basics mailing list archives
Re[2]: how nmap can know my firewalled servers ?
From: Thierry Zoller <Thierry () Zoller lu>
Date: Fri, 14 Apr 2006 10:58:42 +0200
Dear Arturas Zalenekas, AZ> How does TCP protocol work !? How should it replay, e.g. to a closed port AZ> !? With ICMP packet !? Lots of Packetfilters answer with ICMP Administravtively Prohibited, sometimes also leaking their internal IP address by the way.. It is a common way to respond every IP stack I know about will understand that message. AZ> No, it has to answer with an RST. Answering with ICMP is fine, possible and in the wild. -- http://secdev.zoller.lu Thierry Zoller Fingerprint : 5D84 BFDC CD36 A951 2C45 2E57 28B3 75DD 0AC6 F1C7 ------------------------------------------------------------------------- This List Sponsored by: Webroot Don't leave your confidential company and customer records un-protected. Try Webroot's Spy Sweeper Enterprise(TM) for 30 days for FREE with no obligation. See why so many companies trust Spy Sweeper Enterprise to eradicate spyware from their networks. FREE 30-Day Trial of Spy Sweeper Enterprise http://www.webroot.com/forms/enterprise_lead.php --------------------------------------------------------------------------
Current thread:
- Re: how nmap can know my firewalled servers ?, (continued)
- Re: how nmap can know my firewalled servers ? Harrison Holland (Apr 12)
- Re: how nmap can know my firewalled servers ? Nathaniel Hall (Apr 12)
- Re: how nmap can know my firewalled servers ? Alice Bryson (Apr 13)
- Re: how nmap can know my firewalled servers ? Arturas Zalenekas (Apr 13)
- Re: how nmap can know my firewalled servers ? Gregory Boyce (Apr 17)
- Re: how nmap can know my firewalled servers ? Arturas Zalenekas (Apr 17)
- Re: how nmap can know my firewalled servers ? Alice Bryson (Apr 13)
- Re: how nmap can know my firewalled servers ? Gregory Boyce (Apr 13)
- Re: how nmap can know my firewalled servers ? Alexey Eremenko (Apr 13)
- Re: how nmap can know my firewalled servers ? manu (Apr 13)
- Re: how nmap can know my firewalled servers ? Arturas Zalenekas (Apr 13)
- Re[2]: how nmap can know my firewalled servers ? Thierry Zoller (Apr 17)
- Re: Re[2]: how nmap can know my firewalled servers ? Arturas Zalenekas (Apr 17)
- Message not available
- Fwd: Re[2]: how nmap can know my firewalled servers ? John Bond (Apr 19)
- Re: Fwd: Re[2]: how nmap can know my firewalled servers ? Ansgar -59cobalt- Wiechers (Apr 21)
- Re: how nmap can know my firewalled servers ? Alexey Eremenko (Apr 13)
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