The Hacker's Encyclopedia 1998/hackers_encyclopedia.iso/hacking/general/gtmhh1_6.txt

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GUIDE TO (mostly) HARMLESS HACKING

Vol. 1 Number 6

It's vigilante phun day one more time! How to nuke offensive Web sites.
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How do we deal with offensive Web sites?

Remember that the Internet is voluntary. There is no law that forces an ISP
to serve people they don't like. As the spam kings Jeff Slayton, Crazy
Kevin, and, oh, yes, the original spam artists Cantor and Siegal have
learned, life as a spammer is life on the run. The same holds for Web sites
that go over the edge.

The reason I bring this up is that a Happy Hacker list member has told me he
would like to vandalize kiddie porn sites. I think that is a really, really
kewl idea -- except for one problem. You can get thrown in jail! I don't
want the hacker tools you can pick up from public Web and ftp sites to lure
anyone into getting busted. It is easy to use them to vandalize Web sites.
But it is hard to use them without getting caught!

*****************
YOU CAN GO TO JAIL NOTE: Getting into a part of a computer that is not open
to the public is illegal. In addition, if you use the phone lines or
Internet across a US state line to break into a non-public part of a
computer, you have committed a Federal felony. You don't have to cause any
harm at all -- it's still illegal. Even if you just gain root access and
immediately break off your connection -- it's still illegal. Even if you are
doing what you see as your civic duty by vandalizing kiddie porn -- it's
still illegal.
***************

Here's another problem. It took just two grouchy hacker guys to get the
DC-stuff list turned off . Yes, it *will* be back, eventually. But what if
the Internet were limited to carrying only stuff that was totally
inoffensive to everyone? That's why it is against the law to just nuke ISPs
and Web servers you don't like. Believe me, as you will soon find out, it is
really easy to blow an Internet host off the Internet. It is *so* easy that
doing this kind of stuph is NOT elite!

So what's the legal alternative to fighting kiddie porn? Trying to throw Web
kiddie porn guys in jail doesn't always work. While there are laws against
it in the US, the problem is that the Internet is global. Many countries
have no laws against kiddie porn on the Internet. Even if it were illegal
everywhere, in lots of countries the police only bust people in exchange for
you paying a bigger bribe than the criminal pays.

*******************
They can go to jail note: In the US and many other countries, kiddie porn is
illegal. If the imagery is hosted on a physical storage device within the
jurisdiction of a country with laws against it, the person who puts this
imagery on the storage device can go to jail. So if you know enough to help
the authorities get a search warrant, by all means contact them. In the US,
this would be the FBI.
*******************

But the kind of mass outrage that keeps spammers on the run can also drive
kiddie porn off the Web. *We* have the power.

The key is that no one can force an ISP to carry kiddie porn -- or anything
else. In fact, most human beings are so disgusted at kiddie porn that they
will jump at the chance to shut it down. If the ISP is run by some pervert
who wants to make money by offering kiddie porn, then you go to the next
level up, to the ISP that provides connectivity for the kiddie porn ISP.
There someone will be delighted to cut off the b*****ds.

So, how do you find the people who can put a Web site on the run? We start
with the URL.

I am going to use a real URL. But please keep in mind that I am not saying
this actually is a web address with kiddie porn. This is being used for
purposes of illustration only because this URL is carried by a host with so
many hackable features. It also, by at least some standards, carries X-rated
material. So visit it at your own risk.

    http://www.phreak.org

Now let's say someone just told you this was a kiddie porn site. Do you just
launch an attack? No.

This is how hacker wars start. What if phreak.org is actually a nice guy
place? Even if they did once display kiddie porn, perhaps they have
repented. Not wanting to get caught acting on a stupid rumor, I go to the
Web and find the message "no DNS entry." So this Web site doesn't look like
it's there just now.

But it could just be the that the machine that runs the disk that holds this
Web site is temporarily down. There is a way to tell if the computer that
serves a domain name is running: the ping command:

    /usr/etc/ping phreak.org

The answer is:

    /usr/etc/ping: unknown host phreak.org

Now if this Web site had been up, it would have responded like my Web site does:

    /usr/etc/ping techbroker.com

This gives the answer:

    techbroker.com is alive

*************************
Evil Genius Note: Ping is a powerful network diagnostic tool. This example
is from BSD Unix. Quarterdeck Internet Suite and many other software
packages also offer this wimpy version of the ping command. But in its most
powerful form -- which you can get by installing Linux on your computer --
the ping-f command will send out packets as fast as the target host can
respond for an indefinite length of time. This can keep the target extremely
busy and may be enough to put the computer out of action. If several people
do this simultaneously, the target host will almost certainly be unable to
maintain its network connection. So -- *now* do you want to install Linux?
*************************
*************************
Netiquette warning: "Pinging down" a host is incredibly easy. It's way too
easy to be regarded as elite, so don't do it to impress your friends. If you
do it anyhow, be ready to be sued by the owner of your target and kicked off
your ISP-- or much worse! If you should accidentally get the ping command
running in assault mode, you can quickly turn it off by holding down the
control key while pressing the "c" key.
*************************
*************************
You can go to jail warning: If it can be shown that you ran the ping-f
command on purpose to take out the host computer you targeted, this is a
denial of service attack and hence illegal.
************************

OK, now we have established that at least right now, http://phreak.com
either does not exist, or else that the computer hosting it is not connected
to the Internet.

But is this temporary or is it gone, gone, gone? We can get some idea
whether it has been up and around and widely read from the search engine at
http://altavista.digital.com. It is able to search for links embedded in Web
pages. Are there many Web sites with links to phreak.org? I put in the
search commands:

    link: http://www.phreak.org
    host: http://www.phreak.org

But they turn up nothing. So it looks like the phreak.org site is not real
popular.

Well, does phreak.org have a record at Internic? Let's try whois:

    whois phreak.org
    Phreaks, Inc. (PHREAK-DOM)
        Phreaks, Inc.
       1313 Mockingbird Lane
       San Jose, CA 95132   US

       Domain Name: PHREAK.ORG

    Administrative Contact, Billing Contact:
      Connor, Patrick  (PC61)  [e-mail]
      [phone]
   Technical Contact, Zone Contact:
      Hall, Barbara  (BH340)  [e-mail]
      408.262.4142

   Record last updated on 06-Feb-96.
   Record created on 30-Apr-95.

   Domain servers in listed order:

   PC.PPP.ABLECOM.NET           204.75.33.33
   ASYLUM.ASYLUM.ORG            205.217.4.17
   NS.NEXCHI.NET                204.95.8.2

Next I wait a few hours and ping phreak.org again. I discover it is now
alive. So now we have learned that the computer hosting phreak.org is
sometimes connected to the Internet and sometimes not. (In fact, later
probing shows that it is often down.)

I try telnetting to their login sequence:

    telnet phreak.org
    Trying 204.75.33.33 ...
    Connected to phreak.org.
    Escape character is '^]'.



______________  _______________________________ __
___  __ \__  / / /__  __ \__  ____/__    |__  //_/____________________ _
__  /_/ /_  /_/ /__  /_/ /_  __/  __  /| |_  ,<   _  __ \_  ___/_  __ `/
_  ____/_  __  / _  _, _/_  /___  _  ___ |  /| |__/ /_/ /  /   _  /_/ /
/_/     /_/ /_/  /_/ |_| /_____/  /_/  |_/_/ |_|(_)____//_/    _\__, /
                                                               /____/



;
Connection closed by foreign host.

Aha! Someone has connected the computer hosting phreak.org to the Internet!

The fact that this gives just ASCII art and no login prompt suggests that
this host computer does not exactly welcome the casual visitor. It may well
have a firewall that rejects attempted logins from anyone who telnets in
from a host that is not on its approved list.

Next I finger their technical contact:

    finger [e-mail]

Its response is:

    [phreak.org]

It then scrolled out some embarrassing ASCII art. Finger it yourself if you
really want to see it. I'd only rate it PG-13, however.

The fact that phreak.org runs a finger service is interesting. Since finger
is one of the best ways to crack into a system, we can conclude that either:

1) The phreak.org sysadmin is not very security-conscious, or
2) It is so important to phreak.org to send out insulting messages that the
sysadmin doesn't care about the security risk of running finger.

Since we have seen evidence of a fire wall, case 2 is probably true.

One of the Happy Hacker list members who helped me by reviewing this Guide,
William Ryan, decided to further probe phreak.org's finger port:

"I have been paying close attention to all of the "happy hacker" things that
you have posted.  When I tried using the port 79 method on phreak.org, it
connects and then displays a hand with its middle finger raised and the
comment "UP YOURS."  When I tried using finger, I get logged on and a
message is displayed shortly thereafter "In real life???""

Oh, this is just *too* tempting...ah, but let's keep out of trouble and just
leave that port 79 alone, OK?

Now how about their HTML port, which would provide access to any Web sites
hosted by phreak.org? We could just bring up a Web surfing program and take
a look. But we are hackers and hackers never do stuph the ordinary way.
Besides, I don't want to view dirty pictures and naughty words. So we check
to see if it is active with, you guessed it, a little port surfing:

    telnet phreak.org 80

Here's what I get:

    Trying 204.75.33.33 ...
    Connected to phreak.org.
    Escape character is '^]'.
    HTTP/1.0 400 Bad Request
    Server: thttpd/1.00
    Content-type: text/html
    Last-modified: Thu, 22-Aug-96 18:54:20 GMT

    <HTML><HEAD><TITLE>400 Bad Request</TITLE></HEAD>
    <BODY><H2>400 Bad Request</H2>
    Your request '' has bad syntax or is inherently impossible to     satisfy.
    <HR>
    <ADDRESS><A
HREF="http://www.acme.org/software/thttpd/">thttpd/1.00</A></ADDRESS
    </BODY></HTML>
    Connection closed by foreign host.

Now we know that phreak.org does have a web server on its host computer.
This server is called thttpd, version 1.0. We also may suspect that it is a
bit buggy!

What makes me think it is buggy? Look at the version number: 1.0. Also,
that's a pretty weird error message.

If I were the technical administrator for phreak.org, I would get a better
program running on port 80 before someone figures out how to break into root
with it. The problem is that buggy code is often a symptom of code that
takes the lazy approach of using calls to root. In the case of a Web server,
you want to give read-only access to remote users in any user's directories
of html files. So there is a huge temptation to use calls to root.

And a program with calls to root just might crash and dump you out into root.

************************
Newbie note: Root! It is the Valhalla of the hard-core cracker. "Root" is
the account on a multi-user computer which allows you to play god. You
become the "superuser"! It is the account from which you can enter and use
any other account, read and modify any file, run any program. With root
access, you can completely destroy all data on boring.ISP.net or any other
host on which you gain root. (I am *not* suggesting that you do so!)
*************************

Oh, this is just too tempting. I do one little experiment:

    telnet phreak.org 80

This gives:

    Trying 204.75.33.33 ...
    Connected to phreak.org.
    Escape character is '^]'.

Because the program on port 80 times out on commands in a second or less, I
was set up ready to do a paste to host command, which quickly inserted the
following command:

<ADDRESS><A
HREF="http://www.phreak.org/thttpd/">thttpd/1.00</A></ADDRESS</BODY></HTML>

This gives information on phreak.org's port 80 program:

HTTP/1.0 501 Not Implemented
Server: thttpd/1.00
Content-type: text/html
Last-modified: Thu, 22-Aug-96 19:45:15 GMT

<HTML><HEAD><TITLE>501 Not Implemented</TITLE></HEAD>
<BODY><H2>501 Not Implemented</H2>
The requested method '<ADDRESS><A' is not implemented by this server.
<HR>
<ADDRESS><A HREF="http://www.acme.org/software/thttpd/">thttpd/1.00</A></ADDRESS
</BODY></HTML>
Connection closed by foreign host.

All right, what is thttpd? I do a quick search on Altavista and get the answer:

A small, portable, fast, and secure HTTP server. The tiny/turbo/throttling
HTTP server does not fork and is very careful about memory...

But did the programmer figure out how to do all this without calls to root?
Just for kicks I try to access the acme.org URL and get the message "does
not have a DNS entry." So it's off-line, too. But whois tells me it is
registered with Internic. Hmm, this sounds even more like brand X software.
And it's running on a port. Break-in city! What a temptation...arghhh...

Also, once again we see an interesting split personality. The phreak.org
sysadmin cares enough about security to get a Web server advertised as
"secure." But that software shows major symptoms of being a security risk!

So what may we conclude? It looks like phreak.org does have a Web site. But
it is only sporadically connected to the Internet.

Now suppose that we did find something seriously bad news at phreak.org.
Suppose someone wanted to shut it down. Ah-ah-ah, don't touch that buggy
port 80! Or that tempting port 79! Ping in moderation, only!

********************************
You can go to jail note: Are you are as tempted as I am? These guys have
notorious cracker highway port 79 open, AND a buggy port 80! But, once
again, I'm telling you, it is against the law to break into non-public parts
of a computer. If you telnet over US state lines, it is a federal felony.
Even if you think there is something illegal on that thttpd server, only
someone armed with a search warrant has the right to look it over from the
root account.
********************************

First, if in fact there were a problem with phreak.org (remember, this is
just being used as an illustration) I would email a complaint to the
technical and administrative contacts of the ISPs that provide phreak.org's
connection to the Internet. So I look to see who they are:

    whois PC.PPP.ABLECOM.NET

I get the response:

[No name] (PC12-HST)

   Hostname: PC.PPP.ABLECOM.NET
   Address: 204.75.33.33
   System: Sun 4/110 running SunOS 4.1.3

   Record last updated on 30-Apr-95

In this case, since there are no listed contacts, I would email
[e-mail].

I check out the next ISP:

    whois ASYLUM.ASYLUM.ORG

And get:

[No name] (ASYLUM4-HST)

   Hostname: ASYLUM.ASYLUM.ORG
   Address: 205.217.4.17
   System: ? running ?

   Record last updated on 30-Apr-96.

Again, I would email [e-mail]

I check out the last ISP:

    whois NS.NEXCHI.NET

And get:

NEXUS-Chicago (BUDDH-HST)
   1223 W North Shore, Suite 1E
   Chicago, IL 60626

   Hostname: NS.NEXCHI.NET
   Address: 204.95.8.2
   System: Sun running Unix

   Coordinator:
      Torres, Walter  (WT51)  [e-mail]
      312-352-1200

   Record last updated on 31-Dec-95.

So in this case I would email [e-mail] with evidence of the
offending material. I would also email complaints to
[e-mail] and postmaster@ ASYLUM.ASYLUM.ORG.

That's it. Instead of waging escalating hacker wars that can end up getting
people thrown in jail, document your problem with a Web site and ask those
who have the power to cut these guys off to do something. Remember, you can
help fight the bad guys of cyberspace much better from your computer than
you can from a jail cell.

*************************
Netiquette alert: If you are just burning with curiosity about whether
thttpd can be made to crash to root, *DON'T* run experiments on phreak.org's
computer. The sysadmin will probably notice all those weird accesses to port
80 on the shell log file. He or she will presume you are trying to break in,
and will complain to your ISP. You will probably lose your account.
*************************
*************************
Evil Genius note: The symptoms of being hackable that we see in thttpd are
the kind of intellectual challenge that calls for installing Linux on your
PC. Once you get Linux up you could install thttpd. Then you may experiment
with total impunity.

If you should find a bug in thttpd that seriously compromises the security
of any computer running it, then what do you do? Wipe the html files of
phreak.org? NO! You contact the Computer Emergency Response Team (CERT) at
http://cert.org with this information. They will send out an alert. You will
become a hero and be able to charge big bucks as a computer security
consultant. This is much more phun than going to jail. Trust me.
************************

OK, I'm signing off for this column. I look forward to your contributions to
this list. Happy hacking -- and don't get busted!
__________________________________________________________________

Want to share some kewl stuph? Tell me I'm terrific? Flame me? For the first
two, I'm at [e-mail]. Please direct flames to
dev/[e-mail]. Happy hacking!
_______________________________________________________
Copyright 1996 Carolyn P. Meinel. You may forward the GUIDE TO (mostly)
HARMLESS HACKING as long as you leave this notice at the end. To subscribe,
email [e-mail] with message "subscribe hacker
<[e-mail]>" substituting your real email address for Joe Blow's.
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