Re: SP2 Windows firewall and FTP dilemma

From: Wilson (anonymous_at_discussions.microsoft.com)
Date: 10/07/04 

Date: Thu, 7 Oct 2004 08:24:12 -0700

Thanks. I agree that firewall blocks unsolicited inbound
traffic. But if the FTP server uses non-standard ports, my
FTP client does not work in PORT mode when the firewall is
on. If the FTP server uses standard ports, my FTP client
does work in PORT mode when the firewall is on. So, I
wonder if the firewall has special handling on inbound
connection from FTP server port 20.

>-----Original Message-----
>The firewall does not block all inbound traffic - it
blocks unsolicited
>inbound traffic. If it blocked all traffic your Internet
Explorer (port 80)
>would not work either. Since you are connecting to the
FTP server, the
>firewall correctly recognizes that the FTP traffic is in
response to your
>request to connect and allows it.
>
>--
>Richard G. Harper [MVP Win9x] rgharper@gmail.com
>* PLEASE post all messages and replies in the newsgroups
>* for the benefit of all. Private mail is usually not
replied to.
>* My website, such as it is ... http://rgharper.mvps.org/
>* HELP us help YOU ... http://www.dts-l.org/goodpost.htm
>
>
>"Wilson" <anonymous@discussions.microsoft.com> wrote in
message
>news:1cfc01c4ac47$30da39c0$a601280a@phx.gbl...
>> Hello,
>>
>> I use Windows XP Pro with SP2. I have turned on Windows
>> firewall and don't allow exceptions, and check none of
>> the services in advanced settings. But I can still use
>> FTP client in PORT mode to talk with a FTP server
>> outside. The FTP server outside uses standard ports (21,
>> 20).
>>
>> I would like to know if Windows firewall has special
>> handling on FTP. Is it always accept inbound connection
>> from FTP server port 20? Is there any such information
>> from Microsoft official web site? I have searched for 2
>> days but there is no related information about that.
>>
>> Thank you very much.
>>
>> Regards,
>> Wilson
>
>
>.
>

Relevant Pages

  • Re: Hacked? External address knocks on internal private address...
    ... The important part of your message is that FTP is allowed out... ... You open a connection to an FTP Server and logon. ... When you ask the server for a file the server issues a "PORT" command ... so it can open a port on the firewall to allow the incoming Data ...
    (comp.security.firewalls)
  • Re: OT: Trend Micro WFBS beta starting soon
    ... Trend firewall, even set to High, has inbound NetBIOS ports open. ... default 3389 port, web browsing, email, etc. ... it opens inbound NetBIOS connections until the laptop is rebooted. ...
    (microsoft.public.windows.server.sbs)
  • [NEWS] Multiple Firewalls Ruleset Bypass through FTP Revisited
    ... a new attack method affected most leading firewall ... connect to a restrictive port. ... resend control strings supplied by the attacker that a vulnerable firewall ... Connect to FTP server and log on ...
    (Securiteam)
  • Re: SP2 Windows firewall and FTP dilemma
    ... The firewall does not block all inbound traffic - it blocks unsolicited ... If it blocked all traffic your Internet Explorer (port 80) ... Since you are connecting to the FTP server, ... I have turned on Windows ...
    (microsoft.public.windowsxp.network_web)
  • Re: Norton Personal Firewall 2003
    ... > i can exclude the intrusion detection called "port scan". ... > After that i changed the security level to HIGH. ... the firewall checks unsolicited inbound communications attempts. ...
    (comp.security.firewalls)
Loading