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Botnet Targets Web Sites With Junk SSL Connections
angry tapir writes "More than 300 Web sites are being pestered by infected computers that are part of the Pushdo botnet. The FBI, Twitter, and PayPal are among the sites being hit, although it doesn't appear the attacks are designed to knock the sites offline. Pushdo appears to have been recently updated to cause computers infected with it to make SSL connections to various Web sites — the bots start to create an SSL connection, disconnect, and then repeat." SecureWorks's Joe Stewart theorizes that this behavior is designed to obscure Pushdo's command and control in a flurry of bogus SSL traffic.
Probably one of a few things
1) They are looking for a particular vuln to make their bot bigger.
2) They are just testing a DOS.
3) They are actually conducting a DOS.
4) They are trying to make some sort of name for themselves.
5) Combination of the above.
My money is mostly on 1, and some sort of bug in the program causing it to spam the same boxes over and over.
Do they realise that SSL traffic causes a higher load on the server than a regular request? This would be an indication it is trying to bring the site down.
Requesting an SSL connection and then never making it takes a lot less load than actually retrieving a page. It doesn't really suggest a takedown attempt, for which there are superior strategies.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
"Site owners "would just see weird connections that don't seem to make sense," he said. "They look like they're trying to start an SSL handshake, but it comes in malformed and doesn't ever send anything after that first handshake attempt."" Is it possible that they've found a flaw in a specific Systems handling of SSL and are trying to see if the flaw exists elsewhere in an attempt to produce an exploit? I'm not really a security guy, but it seems like they're up to something specific. Otherwise why use SSL exclusively? wouldn't they want to diversify their requests?
Do they realise that SSL traffic causes a higher load on the server than a regular request? This would be an indication it is trying to bring the site down.
Yes, they do. They also don't care. Most botnet authors are self-taught, or only college educated, and are not experienced developers. They don't know how to obscure their creation's activity, because they lack a full understanding of network security. Which is understandable: That isn't in the SDK documentation and example code. Because they lack the skillset necessary to create a protocol resistant to traffic analysis, they go the other way: Flood all the connections and hope those analyzing the logs decide it's not worth the effort to find the needle in the haystack. They know it can be tracked -- they just don't feel its worth the effort to learn how to do it right, when doing it wrong gets them to payday faster and with only a minute amount of additional risk.
#fuckbeta #iamslashdot #dicemustdie
I can honestly say, with experience, that https only takes a trivial amount more CPU time than a http request.
The honest references you will find showing that https was so much heavier than http, was when the blazing fast webservers were 133Mhz.
You're in more danger of the DDoS filling up your pipe than bringing a server to it's knees. The bringing the server down could be accomplished just as easily as a http server. That is unless some genius decided that they needed an entire server farm for http, but only one or two machines for https, which would definately qualify it as "weak"
The folks running the servers should be able to deploy countermeasures of some sort. If a number over some acceptable threshold are illegitimate requests, automatically block them. It's easy enough on a *nix box. I'm not talking about anything in the webserver itself either. The webserver should be able to initiate something as simple as an iptables/ipfilter rule. It's amazing how useful those can be, and if the threshold is calculated appropriately, it won't even bother legitimate traffic.
You are right though, I don't see how these would disguise anything. If you have a list of places that are targets, that makes it more noticeable, not less, even if it is the CnC machine, or a drone.
Serious? Seriousness is well above my pay grade.
Not really.
I've had to parse logs for similar things. Thousands of requests hit a particular exploitable web page, but only one or two IP's are sending further information. It's easy to trim it down the list of candidates, and find who the real problem is.
That's what the feds do in any investigation. They have a broad list of suspects. They eliminate folks until they have their persons of interest, and then down to the guy who they'll be convicting.
Serious? Seriousness is well above my pay grade.
Why is this such a good solution? Have people forgotten how to parse logs? Shouldn't be that difficult to differentiate a connect/disconnect from a connect, send real data, disconnect.
-1 disagree is not a modifier for a reason. -1 troll, flaimbait, redundant, overrated are NOT acceptable substitutes.
most Slashdotters have fairly lax moral standards. Especially when it comes to computers.
Yes, essentially we are all evil . . . now where's that kitten? Er, sorry, I meant robotic, remote-controllable kitten with embedded linux firmware!?
is that because the antivirus program makes the computer crawl to a halt so the bot program has no CPU resources left to run?
Obfuscation isn't good security. But, as any politician will tell you, it's excellent defense.
I tend to agree with you that this sort of thing should still be relatively easy to pickup in logs - on proxies as well as the border routers. A lot of people are probably forgetting that SSL through proxies still needs a CONNECT originserver:443 HTTP/1.x request, which gets logged, even if all of the traffic is encrypted on the tunnel after that.
SSL/TLS at it's core generates "session keys" for communication; a string of random characters. It's possible they're trying to deplete the SSL servers of true entropy for some undisclosed attack; PRNG, for example.
I Browse at +4 Flamebait
Open Source Sysadmin
[Citation needed] The guy that took over torpig has some very nice things to say about the quality of the logging info that suggests the complete opposite, botnet developers are damn good and produce a better product than most code-monkeys.
Some of the malware I've encountered lately (I've got one system unusable until I get around to reinstalling the OS) is very sophisticated indeed. I would admire the designers, if I didn't so badly want them dead.
Does anybody else miss script kiddies?
I would bet that on them not being CMMI certified and not writing their viruses in java...
how long until
I don't get it. Could someone please explain this to me?
If they're trying to disguise their traffic to the command-and-control center, how does this help? If you get a lot of malformed requests from a particular host, then if you're an investigator, it's like the infected computers are advertising themselves as zombies. And if they're sending these requests to major web sites, how does this disguise the requests they're making to the (presumably non-major website) control center? Couldn't you just say, "Well, this computer made 300 malformed SSL requests to Facebook, Twitter, et cetera, and one malformed request to , let's find that guy!"
I'm seriously confused.
I don't believe in time. It's a grand conspiracy designed to sell watches.