Penetration Testing mailing list archives
Re: RE: PIX and ttl
From: "Fernando Cardoso" <fernando.cardoso () whatevernet com>
Date: Sun, 27 May 2001 21:01:53 +0100
[...]
I am running load balanced web servers behind a PIX. I have never been able to identify the server OS with NMAP. Is there a secret? I am aware of doing banner checks. The scenario would be someone doing automated scans for Linux and using NMAP to put known Linux hosts into a file.
NMAP scans for hosts beyond "stateful aware" firewalls is quite difficult. The first problem lies in the firewall design. If a packet is not in the connection table and it's not a SYN packet it is simply droped. The other problem is TCP options. Most firewalls will drop those packets also. In a recent pen-test I realize that Win 2k hosts beyond a PIX, would only respond to NMAP test #5, the only one that uses a standard SYN, while if those boxes where outside the filtered network, they would reply to all 8 tests. The work around is break in and NMAP from the internal network ;) _____________________________________________________________________ INTERNET MAIL FOOTER A presente mensagem pode conter informação considerada confidencial. Se o receptor desta mensagem não for o destinatário indicado, fica expressamente proibido de copiar ou endereçar a mensagem a terceiros. Em tal situação, o receptor deverá destruir a presente mensagem e por gentileza informar o emissor de tal facto. --------------------------------------------------------------------- Privileged or confidential information may be contained in this message. If you are not the addressee indicated in this message, you may not copy or deliver this message to anyone. In such case, you should destroy this message and kindly notify the sender by reply email. ---------------------------------------------------------------------
Current thread:
- PIX and ttl Fernando Cardoso (May 24)
- RE: PIX and ttl Jason Lewis (May 25)
- RE: PIX and ttl Fernando Cardoso (May 25)
- Re: PIX and ttl Konstantin Rozinov (May 27)
- RE: PIX and ttl Jacek Lipkowski (May 25)
- RE: PIX and ttl Jason Lewis (May 26)
- RE: PIX and ttl Fernando Cardoso (May 25)
- <Possible follow-ups>
- Re: PIX and ttl Fabio Pietrosanti (naif) (May 25)
- RE: PIX and ttl Fernando Cardoso (May 25)
- Re: PIX and ttl Nelson Brito (May 26)
- RE: PIX and ttl Fernando Cardoso (May 25)
- Re: RE: PIX and ttl Fernando Cardoso (May 28)
- RE: RE: PIX and ttl Filipe Almeida (May 28)
- RE: RE: PIX and ttl Dario Ciccarone (May 28)
- RE: RE: PIX and ttl Filipe Almeida (May 28)
- Re: RE: RE: PIX and ttl Fernando Cardoso (May 28)
- Re: RE: RE: PIX and ttl Eugene Tsyrklevich (May 29)
- Re: RE: RE: PIX and ttl Fernando Cardoso (May 28)
- RE: PIX and ttl Jason Lewis (May 25)