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Phishers Build Deceptive Links with DNS Wildcards
1sockchuck writes "In the continuing evolution of the phisher, the latest scams are crafting deceptive email links that include a bank's URL, but send victims to a phishing spoof site. The phishers are combining wildcard DNS, URL encoding and redirection services to construct the URLs. Netcraft has examples of emails that presented barclays.co.uk in the URL but sent clicks to a spoofed page at a server in Moscow. A DNS cache poisoning attack over the weekend also highlights the potential use of DNS tricks in 'pharming' (phishing using redirection rather than bait emails)."
Wow! Talk about a great opportunity to educate the masses - now we've just gotta pharm the www.microsoft.com/help website to www.slashdot.com!!! ;)
cat life | grep joy >> memory
Tell the bank that you won't be reading any emails from them, and that they'd better send you snail mail or phone you. If they say that won't be possible, just go elsewhere and let (a) the first bank know why you won't bank with them, and (b) the second bank know why you are banking with them. Provide this information in letter format.
I could see how this would be very confusing for most people. What one of the redirectors does, is actually load the normal bank page from the bank's server, and then load a pop up with a form to submit private details from the phisher's server. The site is down, so I can't check it, but I would imagine that the pop up window is made so that the Address bar is not showing and people can't easily see that it is a bad URL.
Portland, North Dakota Puppies
Don't enter sensitive information into a form linked from an email.
Time to scrap this whole "DNS" thing. I don't know what it is, but it sounds dangerous.
Just a little while ago Network Solutions thought it would be cool to redirect all nonexistent domains to a valid host in the form of website?
Remember when ICANN even thought of listening to Network Solutions?
Hope you do. Mental Bookmark.
After sending all my money to various Nigerian organizations, I wish I had some money for someone to siphon in a phishing scam!
I'm a big tall mofo.
is that they aren't so simple. They are also not logical common sense rules either. The phishing site might look exactly like your real site. Plus, the url might look right if the Phisher used a trojan to install a hosts file on your box.
If this isn't solved definitively, it could destroy e-commerce.
Avoid Missing Ball for High Score
DNS cache poison can be effectively stopped by using the correct DNS caching program. Basically, it is important to use a strong psudo-random number generator to determine the DNS query ID. Ideally, we have the same psudo-random number generator determine the source port of the DNS query.
To the extent of my knowledge, only two recursive DNS servers have this level of DNS poison protection: DjbDNS' dnscache and MaraDNS.
It is also important to have bailwick protection. Basically, the recursive DNS server needs to look at a DNS reply, and filter out any answers not in the bailwick. Older DNS servers (and possibly poorly written embedded DNS caches and recursive servers) will get a reply like "www.paypal.com has the ip 10.1.2.3" to the question "what is the ip for www.phisherscum.com?", and incorrectly cache the data for www.paypal.com instead of saying "I didn't ask for paypal.com's ip, so I'll ignore this data as being out of bailwick".
Additionally, it improves security to restrict which IP addresses are allowed to make remote DNS queries. This is best done at the firewall level (don't allow any UDP connections to port 53 from the internet at large unless you have some domains hosted by the machine in question). This stops malicious servers sending a large number of requests to your dns server for www.paypal.com, and a number of bogus answers "www.paypal.com has the IP of some phishing site in China; remember this until 2007", until one of the answers looks valid and fools your DNS server.
In summary, by using a secuirty aware DNS resolver, you can minimize, if not eliminate the chances of being vulnerable to bogus DNS data.
No, the problem is this: html email. What's wrong with plain text? I'm serious.
I've often thought it was weird that the credit card company would call me, and ask all kinds of questions to make sure I'm really me, before they would tell me/ask me something (like make sure that it was really me who made a big purchase or whatever).
I usually ask them to give me some info from my file to prove that they actually are the credit card company they appear to be, or I call them back using the number in the official documentation.
I think passwords/authentication have to work in both directions. Perhaps e-banking would be more secure if the banking site had to show you proof of authenticity (for example, you ask the system a question about your file, and see if it responds correctly). In practice, this might involve some additional headaches, but I think it could work.
Perhaps the simplest scheme is that you enter your login info, but if you then complete a transaction without getting back the "correct" authentication answer, you call your bank immediately... they block the transaction, you change your password, and it is flagged immediately as a scam.
Thoughts?
The recommended solution to this problem is to bypass DNS and type in all IP addresses by hand.
I can sell you attractive hand made table of domain to IP mappings for the top 25 sites on the internet for just $5!
For this, it'd see they were in a similar range and not be too worried. If it suddenly noticed google was going to 192.168.1.100 (meh) then it would throw up alarms, "This site has a radically different address". Of course, that would be the defaults, there would be options to have it alert you for all ip changes and show you the list of past ips, optionally look it up on arin/ripe/apnic and see who owns the ip, all sortsa stuff.
Preferably it'd come with a list of known good sites, for paypal and a few banks or whatever.
I think a firefence would work a lot nicer than just the spoofstick, but I know NOTHING about coding one, just about what I'd want it to do.
For context, click Parent.
Spoofstick is a Firefox extension that might help in avoiding phising scams. It displays "the most relevant domain information". Looks like its available for IE too.
Did you change your host file to get work done, only to end up memorizing the slashdot ip? Happens to the best of us.
2*31*37*263
I tell anybody who will listen - If you want to log in to your bank, then go to your banks URL yourself, manually, without the aid of a click-thru in an email or another website. Type in yourself. I doubt I am redundant enough but I try. We should be able to get to the point that nobody would ever click on an URL in an email to get to their bank or anything else on the web that has some connection to their money or wealth or whatever.
http://www.busyweather.com/
Hello,
0 8/0052235&tid=95
This is an autmated letter from Bank of America. We need you to confirm your information. Please log in here by copying and pasting the link below:
http://bankofamerica.com|index.cfm|sid=1 00201952820932.slashdot.org/article.pl?sid=05/03/
Thank you for your time,
Bank of America.
Paypal got this right. When the Phishers started going after them in earnest, they sent a bunch of e-mails to registered users saying "Paypal will never ask you to click on a link in e-mail". And all their e-mails about transactions or special offers say "If you would like to do this, enter www.paypal.com in your browser, and then click on tab $foo and then link $bar". It's a bit more effort for the consumer, but it eliminates the "Is this a real or fake e-mail" problem - if it contains any hyperlink at all, it's fake.
My credit card does the same thing. I get automated notifications that say "Your new statement is available online. To access it, go to www..com, and click on "My Statement".
There is no sig, there is only Zuul.
My solution to this problem (since I have a girlfriend that likes to click anything interesting) was to have my mail server redirect all links embedded in incoming messages to a local page that says "don't do that." I also strip all attachments, executable or otherwise, and stick them in a protected folder on the server. That way no-one can click on a link, or accidentally execute an attachment.
The higher the technology, the sharper that two-edged sword.
To do this, I use Acme Software's http_load. http_load takes, on its commandline, a filename containing a list of URLs to request. It then proceeds to send GET requests just as fast as the server can handle them. The trick is to use my Perl script to generate the http_load "loadfile".
First, my script. This could definitely be improved so that it fashions names and street addresses from dictionary words. For now, I just use random junk. To make this script work, you need to look at the phishing scam's HTML source. Find all INPUT tags. Any TYPE=HIDDEN name/value pairs must go in the url_base definition, since the server expects these to be static. The rest (all of the form fields) should go in the @inputs array.
I have another script that uses LWP::UserAgent to make the requests, which I wrote when a crafty phisher rejected submissions where HTTP_REFERER was not his phorm.
E-mail me with questions c-j-s-n-e-l-l_A-T_-_g-m-a-i-l_D-O-T_C-O-M
Chris
phucked (v. tr.): To be taken advantage, betrayed, cheated or victimised by a phishing scam.
Going from 32 bits to 64 bits is a direct upgrade.
Going from Text to HTML is switching technologys.
If you rename a text file from hello.txt to hello.html and pull it up in your web browser you will lose all the formating as HTML expects you to do formating with HTML commands.
32 bits to 64 bits just means your computer can hold more information in one registar.
Also there is nothing stopping a kernel hacker from modifying Linux to store the time/date in two 32 bit regestars instead of one.
Text to HTML is like the diffrence between walking and riding a bike. To edit HTML you still need text. So if an issue were to crop up with Text (like the 32 bit time bug) not only could we not switch to HTML to fix it HTML would be screwed as well.
HTML is a good technology that (IMAO) has been been pushed too far too fast.
But it's not a replacement to text only a better choice when text won't do the job.
Kind of like how a desktop PC dosen't replace a pocket calculator.
And on that note I've been writing my documents mostly in HTML for 10 years now and using a PDA for the last 3.
And I still have a solar powered calculator and get all my e-mail in text.
I don't actually exist.
How do you tell bad bits of html from good bits? As long as there are links, it's possible to phish. Some of the phishers use fairly obviously bad urls if you read as plain text, but if you let them display their image and link it's a faked Sunbank link (or somefink).
The easiest thing is to turn off html, turn off display of inline images, and turn on display of full headers.
People (and companies) send way too much garbage as html or attachments that would be just fine as text. I got into the habit of using text as much as possible when working on a proposal with a bunch of astronomers who don't use MSOffice except at gunpoint. It works great, especially if you use things like sentences, paragraphs, and punctuation.
It would be trivial for the spyware which is rampant on the average user's wintel PC to alter their network settings to point the user at custom DNS servers run by the spyware companies. These could act as dns caching proxies for the most part, but then selectively fail to resolve sites the spyware companies don't want you to see, selectively redirect your queries to the webservers they do want you to see, and in the hands of the nefarious, spoof your bank site too. Until the massive gaping holes in the average user's wintel PC are closed, complex infrastructure exploits are really a waste of time. It's so much easier just to seize their PC and have your way with it.
11*43+456^2
"How do you tell bad bits of html from good bits?"
Check the evil bit in the TCP/IP header.
Need Mercedes parts ?
No. That is not cache poisoning, since it doesn't poison a cache. All DNS servers will cache records that they had to look up. It works like this: Someone queries a DNS server, asking what IP an address maps to. This DNS server doesn't know, and must query another server to find out. Our DNS server sends the query out to another DNS server that would know the answer (the authoritative server for that domain) and waits for a response. When it receives this response, it answers the original query and caches the response so the next time the same query is made it has the answer.
What the attacker does is sends out several (as in, a LOT of) queries to a DNS server for a name, say bank.com. Then, the same attacker sends out several (!) spoofed answers to this query, saying that bank.com maps to a certain address, which is actually some server the attacker controls. The goal is that your bogus response will beat the real response and be accepted by the target DNS server. If the attack is successful, this bogus answer is cached, so when someone else goes to look up bank.com from that particular DNS server, they get the IP of the attacker's server.
The trick is that a DNS server will pick a random number that it assigns to the query sent out to the next DNS server. The response must contain this number for it to be accepted as authentic. The attacker very rarely can know what that number is, hence the large amount of query and answer packets that must be sent out (you are essentially trying to get lucky and hope that one of your fake response packet's number matches one of the server's query packets). In a perfect world, these numbers would be truly random and an immense amount of bandwidth would be required to get enough packets to the server to have a shot at guessing correctly. However, many of the DNS servers pick random numbers out of a much smaller field than they should.
You can either complain, or do nothing. You don't get both.
Serious yes, but been around a long time.
:-)
One example of a cache poisining attack is for a DNS server to provide 'extra answers' for a query.
eg: dns resolver (for an ISP) asks ns.network.net for the records for www.network.net, because some user wants to look at it. No problem it says, and gives back the address of www.network.net.
However, if ns.network.net was malicious, it might also give the address of www.bank.com. If the resolver then accepted this address of www.bank.com and entered it into its cache, well, www.network.net has just taken control of www.bank.com.
(This is why various DNS resolvers have features to ignore additional answers to queries, or ignore answers outside the 'bailiwick' of the server, or things like that. Glue records do make the situation more complex than I've described.)
Suppose through spyware/malware/trojans/virus/whatever, a virus writer were to scan your web browser history, find out what bank in particular you visit, then simply modify the local HOSTS file buried under the system32 directory to point to a specific IP address.
They could then design a login page that doesn't even have to be encrypted (I'm sure most people wouldn't bother to notice) which mimics the real bank's login page. They give one or two "failed" login attempts before redirecting the browser to the real site.
Instead of hijacking dns in some weird way, it simply instructs the local computer to resolve certain DNS entries to something defined locally. After the user thinks they got their password wrong, the phisher's web server redirects the user to the real bank's login page.
This would be something that is entirely possible (virus spread by active x, email, whatnot) and monitors the web browser history for recent activity for a list of known banks, and once that user does their online banking, spoofs the local machine to go elsewhere for subsequent banking. The user doesn't know what happened, and in the meantime types in their banking information that would reveal bank accounts, etc.
Once successfully mined, the bad guys might send an 'abort' sequence to remove all evidence of what happened and move on to the next guy, thus making it hard to track what really happened. Since that entry would be removed from the HOSTS file when that happens, most people would assume they got a string of bad luck for a few login attempts and all seems to be well again (only it's not, since that personal information is now made not quite so personal anymore).
Just suppose this virus created keeps a low enough profile for long enough, even having a firewall antispyware and virus scanner might not help you out.And DNS wildcards are totally sidestepped.
I've said it before...
DNS is the achilles heel of the web. Take down/redirect/spoof/molest DNS, and it doesn't matter how many redundant whatevers and caching whothingies you have.
Nobody's getting to you.
And they may be getting to somebody else.
But DNS isn't glorious, so we'll keep spending the time/money on other things...
vk.
I think spammers/phishers deseerve a special place in hell. I got an email supposedly from first ebay then a different one from paypal and yet another from washington mutual bank(?) concerning my account information. Since I've never set up an account with any of these, I knew instantly it was a phishing scam.
Not only that but when I hover the mouse on the link, it shows the target URL at the bottom and resolved to a fixed IP address (e.g. http://219.44.99.123/ as an example. I just made this address up) rather than point to their respective DNS names.
So (this is the sick and sadistic part comes in), I figured I'd fill out their forms with my "personal" information which is entirely made up. Everything on the form was invented. The name, the address, everything, including the credit card number. After doing that, I sent a copy to abuse@ebay.com, etc.
On one occasion, I got a response email stating there was a problem with my credit card information and I needed to reenter it.
The probem here was that I use the first 4 legitimate digits for visa, but the other 12 digits were entirely fictional and the checksum digit did not match.
I've been toying with the idea of using a credit card number generator and getting past that specific problem, but what if the number that the cc generator picks happens to be a legitimate credit card number and some poor shmuck gets charged? I'm not quite that sadistic.
I wonder if my bank would be gracious enough to issue me a defunct credit card that I could use specifically for this purpose. Failing that, what we need is a list of banned credit card numbers, so when these scammers try to use them, there's a trail that leads the authorities right to their door to haul them away and give them what they deserve.
The way I see it, they took the time to write me for my information which they'd use to screw me, and the least I should do is to return the favor and give them just enough to make them think they got away with it but in fact they expose themselves to getting caught.
Just log in as normal. If any company that I do bussiness with apparantly sends me an e-mail, I don't bother to check if it's real or not, I also don't bother to grab the link, not as much for security but out of laziness (I use pine). I just go and log in to their site as normal. If there is something they need, it'll get my attention.
Thus you don't need to worry about getting phished, but you don't need to exclude a convienent method of communication.
My bank actually doesn't do e-mail, they call me if they want my attentino, security reasons, however Paypal and eBay are both pretty much e-mail only. Not supprisingly, the phishes I do get are usually for those, not my bank.