Re: Kids bypassing firewall via web proxy sites

E. wrote:
> Sebastian Gottschalk wrote:
>> E. wrote:
>>
>>
>>> Such a transfer would require intersite communications to be already
>>> established.
>>> Would it work if google.de/%targetsite was blocked?
>> About any non-blocked website can be abused this way. That's why I
>> stated nytimes.com.
> If it knew what to do with the request.

No, just if it can be used to pass data to someone else in an automated
manner.

>>> How would you
>>> establish communications to a blocked site when proxies are also
>>> blocked?
>>
>>
>> DNS
>
> So you can resolve the IP using a UDP packet. How do you propose to get
> a two-way connection going using a UDP53, and browsing myspace using this?

Get in charge of a certain DNS zone, so having control over the
authoritive DNS answers.

Supposed I want to resolve $base64_encoded_data.somedomain.invalid,
which I'm in control of. The DNS server will send the correct IP and the
response as a TXT, AAAA or PTR record.

>> That's why downloading such utilities being possible, besides
>> circumventing the policies, is no big problem.
>
> As already stated, all downloads being blocked. Sending a UDP packet
> does no equal a downloaded utility.

Stating that clearly: You are *trying* to block downloads. Me happily
assuming that it will generally fail however you try.

>> Anyway, it also requires you to not run any malware^wcommercial software
>> that employs certain ways of scripting without any or any working
>> policies. And I guess many companies are running MS Office. At this
>> point you've already lost.
>
> More allusion, and no proof.

Write a VBA macro doing a LoadLibaryEx() and see what it does to Windows
XP's SRP.
Received on Mon May 1 00:59:48 2006