Re: Bots don't honor 301 :(

2009-01-13 Thread Dan Jenkins




virgins...@vfemail.net wrote:

  
Date: Mon, 12 Jan 2009 19:46:26 -0500
From: "Ben Scott" dragonh...@gmail.com

  
  
not to.  There are orders of magnitude more bots then web servers.

  
  
That's quite a claim.  Do you have evidence for this?
  

I can't say for the types of payload, which would affect your
remediation efforts, carried on the various botnets (which, of course,
varies depending on how the authors and their sublettors use the
botnets), but the Storm botnet was enormous by most estimates. Kraken
the current (known) king is supposed to be(come) bigger. There are
about 186,727,854 web sites currently, though, obviously, far fewer web
servers to host them. To, if the estimate of 50,000,000 in the Storm
botnet (using the higher numbers) was accurate and, for sake of
argument, 10 web sites are hosted on a server on average (purely out of
thin air number I made up), there are 19,000,000 web servers. So, for
sake of argument (do we need a sake for argument?), there are more
botnets than web servers. :-)

References:
Botnet sizes:
http://www.washingtonpost.com/wp-dyn/content/article/2006/02/16/AR2006021601388.html

Storm:
http://www.neoseeker.com/news/7103-worm-storm-gathers-strength/

Kraken:
http://www.darkreading.com/security/perimeter/showArticle.jhtml?articleID=211201307

Websites:
http://news.netcraft.com/archives/2008/12/24/december_2008_web_server_survey.html



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Re: Bots don't honor 301 :(

2009-01-13 Thread David Berube
virgins...@vfemail.net wrote:
 Date: Mon, 12 Jan 2009 19:46:26 -0500
 From: Ben Scott dragonh...@gmail.com

 If you can show me crackbots that
 autonomously coordinate their attacks like [insert random potentially 
 offensive analogy here],
 then there's a chance you may be right about this.

http://en.wikipedia.org/wiki/Botnet

 Where can one find/contact these network abuse reporting systems?
 http://www.google.com/search?q=network+abuse+reporting
 
 Queries like that typically return lots of forum posts in which
 windows users get a lot of stupid answers to a lot of stupid
 questions.  I'd hoped asking that question here would have resulted in
 a smarter answer.

Try whois.

Take it easy,

-- 
David Berube
Berube Consulting
http://berubeconsulting.com
(603)-485-9622
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Re: Bots don't honor 301 :(

2009-01-13 Thread VirginSnow
 Date: Tue, 13 Jan 2009 09:27:27 -0500
 From: David Berube djber...@berubeconsulting.com

  If you can show me crackbots that
  autonomously coordinate their attacks like [insert random potentially 
  offensive analogy here],
  then there's a chance you may be right about this.
 
 http://en.wikipedia.org/wiki/Botnet

This article referrs to DDoS attacks, but that's organizing payload,
not organizing propagation.  What I was referring to was having bots
cooperate to partition and delegate portions of their host space.  For
exmaple, maybe all the bots would agree only to probe and compromise
IP addresses whose last octet is the same as their own IP.  That would
create 254 separate address spaces, and decrease the effectiveness of
any one tarpit by a factor of 254.  However, it would still only take
254 tarpits to cut the number of compromised hosts (on average) in
half.

  Where can one find/contact these network abuse reporting systems?
  http://www.google.com/search?q=network+abuse+reporting
  
  Queries like that typically return lots of forum posts in which
  windows users get a lot of stupid answers to a lot of stupid
  questions.  I'd hoped asking that question here would have resulted in
  a smarter answer.
 
 Try whois.

Yeah, that's typically how the smart folk answered the question.
Unfortunately, whois isn't integrated, which makes it hard to automate
abuse reporting. :(
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Re: Bots don't honor 301 :(

2009-01-13 Thread David Berube
virgins...@vfemail.net wrote:
 Unfortunately, whois isn't integrated, which makes it hard to automate
 abuse reporting. :(

Unfortunately, automated abuse reporting lends itself to being abused by 
the very people it should, in theory, protect against. :(

Take it easy,

-- 
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Berube Consulting
http://berubeconsulting.com
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Re: Bots don't honor 301 :(

2009-01-13 Thread VirginSnow
 Date: Tue, 13 Jan 2009 09:18:31 -0500
 From: Dan Jenkins d...@rastech.com
 CC: gnhlug-discuss@mail.gnhlug.org

 botnet (using the higher numbers) was accurate and, for sake of
 argument, 10 web sites are hosted on a server on average (purely out of
 thin air number I made up), there are 19,000,000 web servers. So, for
 sake of argument (do we need a sake for argument?), there are more
 botnets than web servers. :-)br

Yes, but the number of compromised hosts isn't critical - it's the
number of unique scan queues which is important to evading tarpits.
If a botnet has 50,000,000 nodes, is vulnerable to tarpitting, and
scans every IP address on the Internet in exactly the same order, then
a single tarpit would still save 1/2 the hosts on the Internet from
ever being probed.

The crucial element is the *order* in which prospective hosts are
scanned.  Assuming the bot is deterministic, hosts are likely to be
scanned in the same order by every copy of the bot.
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Re: Bots don't honor 301 :(

2009-01-13 Thread Tom Buskey
On Tue, Jan 13, 2009 at 12:00 PM, virgins...@vfemail.net wrote:

  Date: Tue, 13 Jan 2009 09:18:31 -0500
  From: Dan Jenkins d...@rastech.com
  CC: gnhlug-discuss@mail.gnhlug.org

  botnet (using the higher numbers) was accurate and, for sake of
  argument, 10 web sites are hosted on a server on average (purely out of
  thin air number I made up), there are 19,000,000 web servers. So, for
  sake of argument (do we need a sake for argument?), there are more
  botnets than web servers. :-)br

 Yes, but the number of compromised hosts isn't critical - it's the
 number of unique scan queues which is important to evading tarpits.
 If a botnet has 50,000,000 nodes, is vulnerable to tarpitting, and
 scans every IP address on the Internet in exactly the same order, then
 a single tarpit would still save 1/2 the hosts on the Internet from
 ever being probed.

 The crucial element is the *order* in which prospective hosts are
 scanned.  Assuming the bot is deterministic, hosts are likely to be
 scanned in the same order by every copy of the bot.


Even the 1st internet worm (the RTM one) in 1990 picked hosts in random
order.

I've been reading SANS newsbites and Bruce Schenier's blog for awhile.  The
botnets have become sophisticated in recent years.  It's no longer script
kiddies working after school.  It's criminals with professional computer
experience that are getting paid to do this kind of work.

Some of these botnets lease out to other criminals.  They'd want to keep
that revenue stream free from tarpits, etc.  One botnet (that was used for
spam at least) got shutdown for a day when an ISP that hosted most of its
control bots was taken off the internet.  There were some interesting
analyses of what it di to reconnect.

An argument could be made that these botnets are the early appearence of
Cloud Computing.  SETI is another one.
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Re: Bots don't honor 301 :(

2009-01-13 Thread Ben Scott
On Tue, Jan 13, 2009 at 12:00 PM,  virgins...@vfemail.net wrote:
 Assuming the bot is deterministic, hosts are likely to be
 scanned in the same order by every copy of the bot.

  And assuming the bot only ever scans one host, we only have to shut
off that one host and the problem is solved for all time.

-- Ben
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Re: Bots don't honor 301 :(

2009-01-13 Thread Dan Jenkins




virgins...@vfemail.net wrote:

  Yes, but the number of compromised hosts isn't critical - it's the
number of unique scan queues which is important to evading tarpits.
If a botnet has 50,000,000 nodes, is vulnerable to tarpitting, and
scans every IP address on the Internet in exactly the same order, then
a single tarpit would still save 1/2 the hosts on the Internet from
ever being probed.

The crucial element is the *order* in which prospective hosts are
scanned.  Assuming the bot is deterministic, hosts are likely to be
scanned in the same order by every copy of the bot.
  

>From http://www.honeynet.org/node/54:

Most botnets use a topic command like:
  
 1. ".advscan lsass 200 5 0 -r -s"
  
The first topic tells the bot to spread further with the help of the
LSASS vulnerability. 200 concurrent threads should scan with a delay of
5 seconds for an unlimited time (parameter 0). The scans should be
random (parameter -r) and silent (parameter -s), thus avoiding too much
traffic due to status reports. 


Scans are almost always random nowadays. The bots download their
commands from an IRC channel or some other command-and-control channel,
so they don't have the same list of addresses to scan as the others.
The CC spreads the address ranges for scans around to reduce
visibility to behavioral analysis tools.

There are a number of articles, white papers, research topics available
on distributed scanning, address partitioning and management at the
CC end. 

Bots are not deterministic. They get new addresses often. They are
updated with new payloads and new behaviors. Portions of them are
rented out to others who have differing needs (DDOS, spamming, etc.).
Their updates often come from varied sources as those channels are fast
fluxed and thus change constantly  continually. No two bots are
likely to be completely the same. Why would they have them all scan the
same addresses or behave in a strictly predictable fashion? Brownian
motion provides adequate coverage. Spread the address ranges around to
gain greater coverage. Adjust behavior based on success or failure.

Delaying a single mind-controlled foot soldier, or even destroying such
a soldier, does not prevent, or even slow, the battle from continuing
as the swarm is chaotic. It does not need to be lock-step to accomplish
its goals.



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Re: Bots don't honor 301 :(

2009-01-12 Thread Larry Cook
virgins...@vfemail.net wrote:
 I was thinking about accepting the connection, maybe sending out a few
 headers, and then the stalling the connection.

A friend, back in 2003, was having problems with bad bots so I wrote him 
the following script which accepts the connection, logs and emails some 
client info, and then goes into a loop sending a dot every second.  Just 
kicking them out did not seem like enough.  They would just come back or 
go bother someone else.  Felt more like a community service to keep them 
tied up for a while, although at the expense of his hosting service. 
Some would time out quickly, but he had some held for 2+ hours and one 
for 23 hours!

Larry

-
#!/usr/local/bin/perl

require cgi-lib.pl;
require mail-lib.pl;

$| = 1;

print PrintHeader;
print HtmlTop(Spider Trap);

$time = localtime(time());
print p$ENV{REMOTE_ADDR} - [$time] - \$ENV{HTTP_USER_AGENT}\/p\n;

open(LOG,  spidertrap.log);
flock(LOG,2);
print LOG $ENV{REMOTE_ADDR} - [$time] - \$ENV{HTTP_USER_AGENT}\\n;
close(LOG);

send_mail(spidertr...@hostdomain.com, use...@user1domain.com 
use...@user2domain.com, Gotcha!,
Date  Time: $time \n\nRemote IP: $ENV{REMOTE_ADDR}
   \nReferer: \$ENV{HTTP_REFERER}\ \nUser Agent: 
\$ENV{HTTP_USER_AGENT}\);

$counter=0;
$last=0;
while (1) {
 $counter++;
 sleep 1;
 print .;
 if ($counter  $last) {
if ($counter = 10) {
print Gotcha!!!;
$counter = 0;
}
print br\n;
$last = $counter;
$counter = 0;
 }
}

print HtmlBot;
-
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Re: Bots don't honor 301 :(

2009-01-12 Thread Ben Scott
On Mon, Jan 12, 2009 at 9:19 AM, Larry Cook lc...@sybase.com wrote:
 They would just come back or go bother someone else.

#ifdef CURMUDGEON

  They'll do that anyway.

  This is not a effective deterrent.  It's the security equivalent of
masturbation.  It may make you feel good, but that's all it's doing.

  If you really want to do something effective, lookup the owner of
the IP block and contact their abuse desk, and/or report the source IP
address to one of the various network abuse reporting systems.

  But hey, if you're just looking to feel good, by all means,
continue.  Who am I to tell you to stop having fun?

#endif

-- Ben
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Re: Bots don't honor 301 :(

2009-01-12 Thread Thomas Charron
On Mon, Jan 12, 2009 at 10:35 AM, Ben Scott dragonh...@gmail.com wrote:
 On Mon, Jan 12, 2009 at 9:19 AM, Larry Cook lc...@sybase.com wrote:
 They would just come back or go bother someone else.
 #ifdef CURMUDGEON
  They'll do that anyway.
  This is not a effective deterrent.  It's the security equivalent of
 masturbation.  It may make you feel good, but that's all it's doing.
  If you really want to do something effective, lookup the owner of
 the IP block and contact their abuse desk, and/or report the source IP
 address to one of the various network abuse reporting systems.
  But hey, if you're just looking to feel good, by all means,
 continue.  Who am I to tell you to stop having fun?
 #endif

  I remember what I considered one of the most effective efforts to
shut down spammers, by simply taking away the cost insentive to use
the service.  Unfortunatly, it was considered a counter attack, and
hence shut down..

  Anyone recall the name of it?  It compiled URLs which spammers where
pointing to, and basically had *everyone* on the network start pulling
down those web pages.

-- 
-- Thomas
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Re: Bots don't honor 301 :(

2009-01-12 Thread Larry Cook
Ben Scott wrote:
 On Mon, Jan 12, 2009 at 9:19 AM, Larry Cook lc...@sybase.com wrote:
 They would just come back or go bother someone else.

   This is not a effective deterrent.  It's the security equivalent of
 masturbation.  It may make you feel good, but that's all it's doing.

It felt good until you pointed this out. :-(

Larry
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Re: Bots don't honor 301 :(

2009-01-12 Thread jkinz
On Mon, Jan 12, 2009 at 10:53:19AM -0500, Thomas Charron wrote:
   I remember what I considered one of the most effective efforts to
 shut down spammers, by simply taking away the cost insentive to use
 the service.  Unfortunatly, it was considered a counter attack, and
 hence shut down..
 
   Anyone recall the name of it?  It compiled URLs which spammers where
 pointing to, and basically had *everyone* on the network start pulling
 down those web pages.

IIRC that effort was shut down by concentrated counter attacks
by the spammers.  As for the name, all I can recall was it had
the word blue in it, I think.

it was a good idea but lacked sufficient distributed resources
and money to carry on the fight.

It also may have been a questionable technique due to the 
inability to prevent damage to innocent parties. 

For example, Spammer A wants to disrupt the website of someone they
don't like so they implement a small spam campaign on behalf of that
site and report it to the blue-whatever folks.  Result - that
someone's website get DDOS'ed by well intentioned but falsely aimed
folks.

Jeff Kinz.

-- 
Few things are as simple as they appear or as simple as we would
like them to be.
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Re: Bots don't honor 301 :(

2009-01-12 Thread Cole Tuininga
On Mon, 2009-01-12 at 12:41 -0500, jk...@kinz.org wrote:
 IIRC that effort was shut down by concentrated counter attacks
 by the spammers.  As for the name, all I can recall was it had
 the word blue in it, I think.

I believe Blue Frog (http://en.wikipedia.org/wiki/Blue_Frog) is what
you're speaking of.

-- 
Cole Tuininga co...@code-energy.com
Code Energy (http://www.code-energy.com)

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Re: Bots don't honor 301 :(

2009-01-12 Thread Thomas Charron
On Mon, Jan 12, 2009 at 2:38 PM, Cole Tuininga co...@code-energy.com wrote:
 On Mon, 2009-01-12 at 12:41 -0500, jk...@kinz.org wrote:
 IIRC that effort was shut down by concentrated counter attacks
 by the spammers.  As for the name, all I can recall was it had
 the word blue in it, I think.
 I believe Blue Frog (http://en.wikipedia.org/wiki/Blue_Frog) is what
 you're speaking of.


  That was it.  The article reminded me of why they went caput.  I
thought there was some legaleeze reasons as well.  *shrug*

-- 
-- Thomas
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Re: Bots don't honor 301 :(

2009-01-12 Thread VirginSnow
 Date: Mon, 12 Jan 2009 10:35:05 -0500
 From: Ben Scott dragonh...@gmail.com

 On Mon, Jan 12, 2009 at 9:19 AM, Larry Cook lc...@sybase.com wrote:
  They would just come back or go bother someone else.
 
 #ifdef CURMUDGEON
 
   They'll do that anyway.
 
   This is not a effective deterrent.

How so?  If you're keeping a bot tied up talking to you, you're
keeping the bot from probing other systems. (If you're tying up the
bot, you're obviously not vulnerable yourself.)  Some of these other
systems might indeed be vulnerable to the exploit.  To me, it seems
like keeping bots off of vulnerable hosts *would* be providing a
community service.

Granted, if the botmaster is using a multithreaded bot implementation
with CPU/bandwidth quotas, this won't help anyone.  But I really doubt
these bots are that sophisticated.  In fact, having been teasing them
over the past couple of days, I'm learning just how unsophisticated
they really are.

 It's the security equivalent of masturbation.  It may make you feel
 good, but that's all it's doing.

Please don't use the word masturbation to describe something you
think is worthless.  Given the demographics of this list, it's more
than likely that at least one person here finds masturbation
enjoyable, and could take offense to your reference to masturbation as
an empty and unfulfilling experience.

   If you really want to do something effective, lookup the owner of
 the IP block and contact their abuse desk, and/or report the source IP
 address to one of the various network abuse reporting systems.

Where can one find/contact these network abuse reporting systems?
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Re: Bots don't honor 301 :(

2009-01-12 Thread Ben Scott
DISCLAIMER: I always speak only for myself, unless otherwise
explicitly indicated.

On Mon, Jan 12, 2009 at 3:02 PM,  virgins...@vfemail.net wrote:
  They would just come back or go bother someone else.

   This is not a effective deterrent.

 How so?

  What part of come back or go bother someone else is unclear?

 If you're keeping a bot tied up talking to you, you're keeping the
 bot from probing other systems.

  Sadly, botmasters aren't all morons.  They're aware of things like
setting timeout values.  They often don't care because they can afford
not to.  There are orders of magnitude more bots then web servers.

  If you were to wave your magic wand and cause every non-vulnerable
web server on the net to start tarpitting, that would simply mean the
botmasters would implement timeouts that much sooner.

 Granted, if the botmaster is using a multithreaded bot implementation

  They are, just not on the scale you imagine.  Their computer is
every compromised host on the Internet, each host a CPU.

 It's the security equivalent of masturbation.  It may make you feel
 good, but that's all it's doing.

 Please don't use the word masturbation to describe something you
 think is worthless.

  You need to work on your reading comprehension.  Since I apparently
need to spell things out for you: I never called it worthless.  I
said it was not an effective deterrent, and that all it accomplished
was making the operator feel good, and even acknowledged that making
the operator feel good is not necessarily a worthless ambition.

 Where can one find/contact these network abuse reporting systems?

http://www.google.com/search?q=network+abuse+reporting

-- Ben
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Re: Bots don't honor 301 :(

2009-01-12 Thread VirginSnow
 Date: Mon, 12 Jan 2009 19:46:26 -0500
 From: Ben Scott dragonh...@gmail.com

 not to.  There are orders of magnitude more bots then web servers.

That's quite a claim.  Do you have evidence for this?

In order for the scenario you're suggesting to take place, vulnerable
hosts would have to be attacked by *multiple* bots.  Furthermore, the
bots would have to be independent implementations of the same exploit,
unless the author used some pseudorandom process to shuffle the bot's
attack queue.  Otherwise, any repeat attacks would be shadowed by a
tarpit exactly the same as the first attack.

Perhaps a better metaphor for your argument (than masturbation)
would be pulling one cop off of Rodney King.  But the cops attacking
Rodney King were coordinated.  If you can show me crackbots that
autonomously coordinate their attacks like a hateful gang of racist
cops, then there's a chance you may be right about this.

  Where can one find/contact these network abuse reporting systems?
 
 http://www.google.com/search?q=network+abuse+reporting

Queries like that typically return lots of forum posts in which
windows users get a lot of stupid answers to a lot of stupid
questions.  I'd hoped asking that question here would have resulted in
a smarter answer.
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Bots don't honor 301 :(

2009-01-10 Thread VirginSnow
My httpd logs have been bombarded, lately, with probes by crackbots
(mostly for roundcube webmail and mantis bugtracker exploits).  This
got me wondering, What can I do to keep these buggers off my server?

Of course, the iptables -j TARPIT approach came to mind, but that
didn't quite seem creative enough.  Besides, what if one of the
compromised hosts legitimately wants to browse one of my sites?  So I
got the idea to use status code 301 to redirect these bots to
something fun, like:

  
http://cybercrime.fbi.gov/complaints/submit_complaint.php?message=i+am+a+script+kidde+or+robot+attempting+to+compromise+a+computer+at+IP+address,+the+URL+i+am+using+to+do+this+is+$1

So, I set up my servers to trap exploit URLs and 301 them to another
server that I control.  However, the bots didn't respect the 301, and
seemed to treat the 301 much like a 404. :(

So, what if I use a fastcgi program to send the bot a 200 response
with a new Location: header, I wonder.

Has anyone on this list found any fun ways to burn these bots?

(BTW, legitimate bots, like googlebot, *do* honor status code 301.)
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Re: Bots don't honor 301 :(

2009-01-10 Thread Ben Scott
On Sat, Jan 10, 2009 at 10:27 AM,  virgins...@vfemail.net wrote:
 However, the bots didn't respect the 301 ...

  Why should they?  They're looking for vulnerable systems to exploit.
 If they don't get the reaction they want from their probe, they've
established you're not vulnerable, and they move on to the next probe.

-- Ben
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Re: Bots don't honor 301 :(

2009-01-10 Thread H. Kurth Bemis
What about a perl (or python, ruby etc) script that will tail your
error_log, watching for multiple 404's coming from the same IP within a
given timeframe.  If the IP is tripping too many 404's for things that
don't exist, add them to the DROP chain.

I solved a similar problem using iptables rate limiting feature.  Just
slows down the attempts from hundreds/night to about ~8/night.

Just a thought..
~kurth

On Sat, 2009-01-10 at 15:27 +, virgins...@vfemail.net wrote:
 My httpd logs have been bombarded, lately, with probes by crackbots
 (mostly for roundcube webmail and mantis bugtracker exploits).  This
 got me wondering, What can I do to keep these buggers off my server?
 
 Of course, the iptables -j TARPIT approach came to mind, but that
 didn't quite seem creative enough.  Besides, what if one of the
 compromised hosts legitimately wants to browse one of my sites?  So I
 got the idea to use status code 301 to redirect these bots to
 something fun, like:
 
   
 http://cybercrime.fbi.gov/complaints/submit_complaint.php?message=i+am+a+script+kidde+or+robot+attempting+to+compromise+a+computer+at+IP+address,+the+URL+i+am+using+to+do+this+is+$1
 
 So, I set up my servers to trap exploit URLs and 301 them to another
 server that I control.  However, the bots didn't respect the 301, and
 seemed to treat the 301 much like a 404. :(
 
 So, what if I use a fastcgi program to send the bot a 200 response
 with a new Location: header, I wonder.
 
 Has anyone on this list found any fun ways to burn these bots?
 
 (BTW, legitimate bots, like googlebot, *do* honor status code 301.)
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Re: Bots don't honor 301 :(

2009-01-10 Thread VirginSnow
 From: H. Kurth Bemis ku...@kurthbemis.com
 Date: Sat, 10 Jan 2009 15:51:50 -0500
 Cc: gnhlug-discuss@mail.gnhlug.org

 I solved a similar problem using iptables rate limiting feature.  Just
 slows down the attempts from hundreds/night to about ~8/night.

I was thinking about accepting the connection, maybe sending out a few
headers, and then the stalling the connection.  But it's easy to set
connect/read timeouts, even on windows.  That's something the bot
writer is likely to have accounted for.

I could return 200 OK, and send an infinite stream of 0xFF at the bot.
That might overflow its receive buffer or ehxaust its memory.  No one
on this list would happen to know if spambots bounds check their
reads, would they?  (; I might be able to test for it, if there was a
way to detect when the client socket is closed.  Do win32 clients send
a FIN/ACK pair when an app with an open TCP socket unceremoniously
crashes?  If not, I could interperet a FIN packet to mean that the
bot's immune to being drowned with 0xFFs.

I can't spend a whole lot of time on this though.  If there's
something quick and dirty I can put in place that'll take the bots
down, I'll use it.  I'm just not willing to build a full blown
honeypot to do so.
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