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Re: Cisco says attacks are due to operational practices

  • From: Bora Akyol
  • Date: Fri Feb 11 14:08:36 2000

Unfortunately, ssh on linux regularly assigns ports when ssh'ing out from a box
below 1024, I think this is a bug, but make writing firewall commands annoying.

Bora


"John M. Brown" wrote:

> Umm, lets see, hosts are supposed to assign ports for sessions above 1024.
> Ports below 1024 are "priv / root" ports and are assigned for specific
> services.
>
> We filter <1023  >1023 we don't care about so much, except for a couple of
> well known ones.
>
> On Thu, Feb 10, 2000 at 07:02:25PM -0800, Chris Cappuccio wrote:
> >
> > Did anyone even read the post I was responding to ??
> >
> > >On Thu, 10 Feb 2000, John M. Brown wrote:
> > >| We have always built martian filters on our edge routers.  In addition we
> > >| built specific filters for ports that are not used, or are bad on the net.
> >
> > "Ports that are not used" What about when the tcp stack on a particular
> > machine dynamically allocates a particular port for some tcp connection and
> > you are filtering that port ? etc....
> >
> >
> >
> > On Thu, 10 Feb 2000, Paul Ferguson wrote:
> >
> >  | I did't see anyone talking about port-level filtering. What
> >  | I did see, on the other hand, was someone talking about about
> >  | filtering Martian network traffic -- stuff which should not
> >  | be there in the first place.
> >  |
> >  | - paul
> >  |
> >  |
> >  |
> >
> > ---
> > Gates' Law: Every 18 months, the speed of software halves.
> >
> >






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