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Google 302 Exploit Knocks Sites Out
clsc writes "The exploit: Redirect via 302 to another page of your choice, then watch as the URL of your redirect script replaces the URL of that carefully selected page in Google's search results. Once this happens, feel free to redirect any visitor that is not Googlebot to any other page of your choice. Also applies to other search engines as well (not Yahoo! though)."
Web wide malware. The return of Goatse cannot be far behind... Pun intended.
Kindness is the language which the deaf can hear and the blind can see. - Mark Twain
1. post how to generate more traffic to one's website by exploiting a flow in google on /.
...
2. show a "random" ad (336px by 280 px) promoting 'google adsense' clearly stating "how to turn your website into a revenue generator in minutes" at said post.
3. $$$
SELL SELL SELL SHORT!!!!
boy, sending me to the wrong page is such a scary and horrible thing to do. Luckily my browser came equipped with the special "back button" anti-malware plugin.
"Weapons should be hardy rather than decorative" - Miyamoto Musashi
I think that goes for OS's too
Insert MS blame here
Oracle 9iAS and 10gAS are VERY heavy on the 302 redirects (as a way to moderate traffic using mod_oc4j).
/foo, you'd see a redirect from http://www.example.com/foo to http://www.example.com/foo/, but I can see this product borking up search results as its use becomes pervasive in the enterprise.
Most of the redirects are innocuous, for example with an application whose context-root is
Since the product can't be changed, I'd probably change Google's behavior.
Three Step Plan:
1. Take over the world.
2. Get a lot of cookies.
3. Eat the cookies.
It's an exploit if you can't prevent someone from misusing 302, or to filter out malicious uses of 302 from legitimate ones.
You see? You see? Your stupid minds! Stupid! Stupid!
Hey look! Someone forgot to RTFA!
You use 302 to hijack someone else's page in Google's search results. Your bogus ad infested page shows up instead of the actual content the user was searching for (and thought they were going to see), while the real website that you hijacked doesn't get any more Google traffic. That's the exploit.
Dumbass.
Seems like all the hackers are struggling now-a-days. There are no "good" exploits coming out anymore. No directory Unicode transversals.. No Code Red, No Nimda. Not even SQL Slammer...
We haven't had a good exploit/0day in how long? Since the Webdav exploit? Or the RPC DCOM? Now we have to use Google, phishing techniques, and URL redirection. We are scraping the bottom of the barrell apparently.
The use of the exploit isn't just to childishly send people to Goatse - it's about money. What happens when you go to your bank's website and get redirected to an identical-looking website that steals your information?
A site registered and hosted using stolen funds from my credit card is still online following phoned and faxed demands for revocation and refund sent to the registrar/host. Can I somehow use this to send an entire domain to a black hole until the hosting/domain are revoked? It wouldn't be hacking, but it would make me feel a lot better to see the scammers knocked offline. If no one can get to them on google, they can't get any scam income. And what are they going to do -- sue me? That just would result in my slapping them with *criminal* charges as well as a motion for dismissal and a countersuit.
i am a soviet space shuttle
This is totally true.
There are basically two schools of thought in SEO as I've seen it. You can either try and be everywhere (spamming by creating zillions of pages and links) or you can be interesting (like this blog; people want to come here, instead of needing to be tricked).
Unfortunately, most people are about as interesting as watching grass grow, and they know it. So they spam the search engines and aim for the lowest common denominator. Sad, really.
I Want To Believe
Wow. That's a fun exploit... I can't wait to go tell my boss why our site links to a pron site on google.
All kidding aside this could be a major problem for some of the more controversial websites. Akin to the Googlebombing that was just mentioned yesterday this could be the next major attack scheme on the net. Imagine a pro-life site subverting a pro-choice site, Neo-nazi's subverting a site intended for Jewish children, the US government subverting Al Jazera...
Not a whole lot of fun IMHO. I trust google to return what I search for, if this changes I and a whole lot of other nerds are going to be left wandering aimlessly around the net.
If the googlebot scans the redirected page and assigns weights based on the end result page, but assigns the ranking to your original page, then you are essentially stealing pagerank from the proper host.
That is my understanding of the problem, and part of the reason why redirects appear to get higher rankings than simply copy and pasting somebodies content.
As for covert googlebots, I'm sure they exist as R&D items, but doubt they would be setup in the manner you describe.
liqbase
The main thread about this on WebMasterWorld is over 500 posts now.. lots of good info there.
This sig all sigs devours
from tfa:
*it allows a hijacking website to replace pages belonging to target websites in the Search Engine Results Pages*
that's what it does. think about it for a while. sure they could have protection but at the time it seems they DO NOT.
*What does it look like?
The Search Engine Results Pages ("SERPs") will look just like normal results to the searcher when a page hijack has occured. On the other hand, to a webmaster that knows where one of his pages used to be listed, it will look a little different. The webmaster will be able to identify it because (s)he will see his/her page listed with an URL that does not belong to the site. The URL is the part in green text under listings in Google.*
a lot of people use google as a sort of bookmarks page(with keywords they remember), potentially this could hurt them. what it more likely happens if it isn't fixed is that advertisers start to pollute the results even more, eventually leading google to be useless.
world was created 5 seconds before this post as it is.
Anyone that wants to steal your traffic can take advantage of this. Nearly all the sites that I have created in the last year have been purposely hijacked by this and don't show up in any Google rankings. I've learned to live with it despite contacting the jerk responsible who pleaded innocent and said he wasn't very technical and didn't know what was going on.
Historically, good content meant good search engine placement. Now that this little trick is being more publicized, it just decreases the amount of time required for someone to hijack your entire site and remove it completely from the search engine results.
I'm a big tall mofo.
Do you mean this is not www.kuro5hin.org ??
BoD
I didn't even realize that I did this until I read your post. Not that anyone cares, but I only have 4 or 5 regular bookmarks; the rest of the pages I need to goto I either a) remember because the url is so easy or i go there so much (e.g., slashdot, orderyourrussianwife.com, etc) b) do a search for them as needed (e.g. martin vetterli's homepage), or c) use the url auto-complete in the browser.
I've noticed that a lot of my google searches get redirected to an Ebay search page even though the displayed url in the search results is a non-ebay url. I checked the Google cached result and it was not the same as the re-directed page.
It's very annoying as I haven't been able to figure out what is going on. The same Ebay search results show up under dozens of urls in the Google search results
There seems to be a lot of confusion as to why exactly this is such a big deal. A lot of people saying there's no problem or that this is nothing... basically just not understanding the issue. Let me explain:
Suppose you have a small business under the domain http://xyz.com/, and search engines bring you a lot of traffic because you rank high for keywords in your market. You have a lot of people out there linking to you, a lot of satisfied customers, good content on your site. You're always in the top 10 somewhere when people search for "xyz widgets".
Well, this issue with Google makes it very easy -- incredibly easy -- for someone to knock your site out of the rankings entirely. And I mean for *everything*, to where searching for your own company name in quotes literally buries you hundreds of pages deep in the results. We're talking sites going from getting 1000 unique hits to 10 overnight.
And here's the kicker: It requires absolutely no technical knowledge, no time investment, and is perfectly legal...
All I have to do is have another domain handy that is roughly as popular as yours. And I make a "links" page, like one of those directory services, that lists your website. But instead of being a normal hyperlink, it's a CGI (or PHP or ASP or whatever) script that generates a 302 redirect to your domain... Now, these are very simple, common scripts. One-liners that you can download from cgiscripts.com and stick on your server. The original intent of these scripts is to track which links are being clicked on your site. But now they've found a new use, because when Google gets that 302, all hell breaks loose.
See, according to the HTTP spec, 302 is a *temporary* redirect, which means Google is supposed to interpret whatever content it finds at the 302 target (your site) as really belonging to the URL of the source (my site). Google is just obeying the spec strictly here, and with devestating results. Why? BECAUSE THE DUPE FILTER NOW KICKS IN! You see, Google has a "dupe filter" that says if the same exact content is found for two unique URLs, then one of the URLs is obliterated in the rankings. Because after all, searchers don't want to be finding the same content over and over. If that happens, they'll start using a different search engine. But Google, sticking strictly to the HTTP spec, doesn't know who the content really belongs to when it gets a 302.
So Google essentially flips a coin. And if it comes up tails, say bye-bye to your domain in the rankings. Your *entire* domain. Because the dupe filter isn't limited to just the page that the 302 is pointing to -- it applies across your entire domain.
These 302 "exit-link-trackers" are all over the web. They've been used by webmasters for years. But it's just recently that Google has started treating 302 this way, so it didn't have any bad effect before. But now it kills you.
The funny thing is, the solution seems pretty simple: Just stop treating 302s this way if they point to a different domain. But for whatever reason Google isn't listening. Hopefully the press that's being generated now will give them the kick in the ass that they need.
Well, I knew about the 302 bug (in fact, it's been known for months in professional webmaster circles).. so, I did an allinurl:mydomain.com/mypage.htm search on Google to find the culprit. Low and behold, it was some blog page about one PR below my page with a script that redirected through a 302. The catch was that this redirect script ONLY worked if you clicked on it from the blog itself - if you clicked on it from the Google SERPs you got a 500 server error.. so in effect, Google misidentified the redirect page as my actual page and then subsequently tried to spider it from the URL directly and got a 500 error.. the result being that I was dropped from the index. Was this malicious? Hardly - the webmaster had compiled a small list of cool, useful links - not knowing that his buggy redirector was killing those sites off.
So whaddya do? I tried emailing the webmaster but everything bounced. It looks like he was out of the country. I tried giving Google feedback, but frankly that's just like offering up a prayer to the Great Google God - so I also used the BASE HREF trick mentioned in the article, and after a few days the page came back in the index as normal. So, either that trick worked or the Google God answered my prayers. I'm guessing at the former.
Never email donotemail@WeAreSpammers.com
This "exploit" isn't very interesting and the author really doesn't seem to have a good grasp of the HTTP protocol design, the end-to-end model, or the internet in general.
I'd be very careful before I blindly changed all my redirects to 301s. The semantics behind a 301 and 302 are VERY different and unless you want people to replace the original URI with the target in your 301s, forever, you might be entering a world of hurt.
From RFC 2616 -- HTTP/1.1 :
10.3.2 301 Moved Permanently
The requested resource has been assigned a new permanent URI and any future references to this resource SHOULD use one of the returned URIs. Clients with link editing capabilities ought to automatically re-link references to the Request-URI to one or more of the new references returned by the server, where possible. This response is cacheable unless indicated otherwise.
10.3.3 302 Found
The requested resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. This response is only cacheable if indicated by a Cache-Control or Expires header field.
This is a common theme in the high-tech world; Joe Hacker figures out a problem and a 'solution'. Problem is, they don't understand all the implications of the solution. That doesn't stop them from yelling loudly about the solution. Without a comprehensive explanation of the impact of the 'solution' you might be just causing yourself harm in other areas down the road.
Education and thorough analysis are always a good idea when you are dealing with complex systems that might have emergent behaviors. This is certainly one of the bigger pet-peeves at the IETF and with the IESG.
*waves hand*
"This isn't the webpage you are looking for."
I have seen this exploit used in a variety of ways.
For instance, this kind of redirect could be used to highjack Amazon.com - the user types in Amazon into a search box, sees the title and snippet that matches amazon, clicks it, the hijacker gets affiliate commission credit for sending people to amazon.com.
Basically the 302 link makes the linking site appear to host the target site's page, and it replaces it in the search results.
You can pretty much do it for any site. In the case of Amazon, they'd likely void your affiliate commissions - if they noticed (which they would eventually) but if you did it for a few days before, say, Christmas, and took it down after it worked, you might net 8 - 15K in a single day.
Another danger is a malicious site whose redirect page sniffed for JavaScript. User Agents with JS deactivated would redirect straight to, say, CNN, if the UA accepted JS, it could start loading one of the many spyware "tools" that forcefeed affiliate tracking cookies into the user's computer, or much worse.
There are tens of thousands of searches for "cnn.com" in the search engines a day - even if the highjacker was able to only replace CNN for a day, the harm would be widespread.
Unfortunately, the Google PageRank is not considered when ranking the sites, as Google basically considers www.example.com/302.php?www.cnn.com to actually be www.cnn.com - it will show CNN.com's backlinks when your query backlinks for the hijack url, for example.
::.. check out some Cell Phone Reviews
Easiest way to fix it is to not follow 302's since 302 means "The requested resource resides temporarily under a different URI."
.
I would imagine that this could cause a problem with getting a website into the listing that is in the process of moving, but if Google simply waited until it's an actual 200 status code, then redirections would get ignored (since they're not
From the W3C document:
The temporary URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s).
Again, and since even the temporary URI doesn't have to be given, 302's should be ignored. Even 301's and 303's are not acceptable since the new URI doesn't have to be given.
The harder way to fix it is to only accept 3xx response codes that give the new URI in response. Even then, I assume it's possible to still fake a 200 response code if you modify the http daemon, and make a transparent redirection... thus fooling the search engine in every respect.
In my opinion, I don't see a way around it unless you include signature files or such... but even if you used and SSL connection, it's probably still exploitable.
I guess you're damned any way you look at it.