Blocking Win95 hosts [WAS: Lazy network operators - NOT]

Mon Apr 19 04:03:29 UTC 2004

On Apr 18, 2004, at 11:40 PM, Matt Hess wrote:

> <late-night-humor>
> I was amused at this and decided to look real quick.. OpenBSD's pf can 
> block on OS fingerprints.. effectively doing exactly what you are 
> kidding about (at least I'd hope so.. well, maybe) even in the man 
> page example they put:
>
> # Do not allow Windows 9x SMTP connections since they are typically
> # a viral worm. Alternately we could limit these OSes to 1 connection 
> each.
> block in on $ext_if proto tcp from any os {"Windows 95", "Windows 98"} 
> \
>       to any port smtp
>
> The OS fingerprint list they have is rather extensive..
> </late-night-humor>

Ya know, I do not think that is such a bad idea.

Does anyone have any stats on the number of "real" MTAs that use Win9x? 
  Or of the "real" MTAs that show up as Win9x on this fingerprint?

-- 
TTFN,
patrick