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Archive for the 'Phishing' Category

Phishing With Google Wave

Wednesday, February 10th, 2010

Hat tip to cyberlocksmith for this post. He pointed me to a good article on how to phish Google Wave users using malicious gadgets. This is precisely what Tom Stracener and I were talking about in our presentation at DefCon and Blackhat a few years back - except this is for Wave instead of iGoogle. Either way the point is the same - when you let other people control content that is embedded in your site, you are at the mercy of whatever they chose to do within that gadget. In this case, they can pop the user out of the iframe and present them with a duplicate of the sign-in page. The vast majority of users would fall for this kind of attack too.

I really don’t mean to harp too much on Google specifically for this stuff (in as much as I have countless times in the past held them accountable for their crappy security). There are lots of other companies and websites that are moving to user supplied gadgets in an iframe as if that makes them safe. Maybe some variant of HTML5 + some trickery can solve these problems, but there’s a lot of legacy users who won’t be able to support those standards for a good long while. In the mean-time, we just continue to see more vulnerable code being outputted by Google and their peers and the only saving grace is that no one has yet decided to take advantage of their security flaws. Scary. But I’m sure a blacklist will solve their problems if and when they do get attacked, right? Right?

Redirection Report

Wednesday, July 16th, 2008

Brian Krebs had an interesting report over at the Washington Post that cited a report from Indiana.edu about how redirects are in quite an abundance. Well, anyone who has worked in this field for any length of time should know that perfectly well, but it’s still interesting to get some validation from the researchers at Indiana.edu who specialize in anti-phishing research. Here’s the rub from Brian’s article:

Indeed, some of the Internet’s biggest Web sites — particularly Google — used to host large numbers of open redirects.

“Used to”? I know I’ve laid it on thick over the last few years, but I’m amazed people still think Google has somehow magically fixed problems that it never got around to fixing. Redirects are not fixed, XSS is not fixed. These issues still exist all over Google and Google’s web properties. But in case someone doesn’t believe me, here’s an example I whipped up in about 10 seconds that redirects to a random eBay auction from Google’s image server as a for instance (make sure you enable JS for the full effect).

It’s good to see people are finally understanding this in the main stream media, but let’s not give credit to companies that are clearly undeserving of it (both historically and currently). I’ll be the first one to stand up and give applause when we see these issues closed once and for all on Google even if it truly is just one company out of the vast untold wealth of sites out there that are vulnerable. But if it really is aiding phishers - and it is - the only way we are going to get ahead of it is by taking responsibility for our own sites. That’s especially true if we intend to be the be all end all of trustworthy advertising giants that Google aims to be.

Key Point SMiShing

Sunday, June 1st, 2008

Yesterday, my gfnd got a SMiShing text to her phone against Key Point Credit Union. The obvious tip off that this was an attack was that she doesn’t have an account with Key Point, not to mention the other clues. This is the first instance of it in the US I’ve heard of, although I’d be surprised if this was the first example of it. The number it was from was 905-392-8040. Unlike normal phishing though, it’s much harder to report the issue. Most people wouldn’t have the first clue how to log, forward or respond to the SMiShing attack.

Dear Key Point Credit Union Customer, we regret to inform you that we had to lock your bank account access. Call 800-482-0452 to restore your bank account.

Just another thing to be worried about. I have no idea what the lift on SMiShing attacks are compared to their online variants, but it’s an interesting phenomena. Since email addresses of SMSs are fairly easy to predict, it’s fairly simple to re-purpose spam gateways that are designed exactly for this purpose. The only trick is gathering enough mobile phone numbers.

Phishing Site in Email

Thursday, May 15th, 2008

I was looking at a phishing email last night for OANDA FXTrade. At first glance I could see something a little different about it. Instead of linking directly to the phishing site in the email, it contained an attachment (an html file) that you are supposed to double click on. The page is a flat HTML page, with nothing of substance on it, other than a form that tries to get you to submit your data to http://0x47f865c1/webview/images/fxtrade.php (which automatically redirects you to the correct website, if you go there directly).

That’s a fairly clever implementation of a phishing email, because the phishing page is actually on your local computer, not on the web. So it’s harder for anti-phishing researchers to find anything of interest on the remote computer, or even verify that it is a phishing site. But I think I must be getting a little jaded because as soon as I saw the html file I was actually disappointed. While clever since the HTML file contains the phishing site, why on earth wouldn’t they put malicious code in it? Think about it, if someone is dumb enough to open a HTML file on their local computer, why wouldn’t you use it to install malware or something equally bad? To me it just seemed like a no-brainer. I suspect these malicious techniques will eventually converge, but for now, I don’t think the phishers understood exactly what power they had.

Mozilla Fixes Referrer Spoofing Issue

Friday, March 28th, 2008

Good for Mozilla - they recently fixed a very odd referrer spoofing issue that I was talking about back in January. It wasn’t exactly ten days, but who’s counting. ;) But referring URLs are a tricky beast. I see them being relied on an awful lot. I also see a lot of misbehaving robots in my logs that seem to think they understand what a referring URL is, but yet… they don’t.

One good example are robots that forget how Google works: http://google.com instead of http://www.google.com/ (notice the “www.” and the trailing slash are missing.) Also spammers, please note that as of today and every other day I have checked I have never once been a link on the front page of Google’s website and if it did happen, there will be a great earthquake; and the sun will become black as sackcloth of hair, and the moon will become as blood, so we best not even talk about such things. There’s tons of this garbage in my logs all day long. It’s almost surprising to me that the bad guys would bother. If anything it makes it stand out like a sore thumb. Yet, I do see companies making security decisions based on referring URLs. Kinda scary given how many reasons referring URLs might be wrong or non existent.

As a side note, when I attempted to use the :username@ trick for phishing it did not silently drop the username, it actually redirected me to the search engine, which is actually pretty appropriate behavior given that it’s malformed. I’m glad someone was able to reproduce it because I had a hard time proving to myself that it was even something widespread enough to talk about. Anyway, Kudos to Mozilla for the patch!

Human CAPTCHA Breaking

Tuesday, March 11th, 2008

After almost a year, I’ve decided to re-visit an old post I wrote regarding solving CAPTCHAs for cash. Specifically, people that want to use Google or Yahoo to spam, by automatically signing up for thousands of email accounts which requires humans to solve CAPTCHAs for them. According to MessageLabs, webmail based spam represents approximately 4.2% of all spam on the Internet - pretty significant.

There have been a number of articles on the Internet about automatic solutions to CAPTCHAs, but honestly, I find those stories somewhat dubious at best. Firstly, I don’t believe the solution rate is all that high as some people are claiming (it’s possible, but I don’t believe it’s happened for Gmail or Yahoo mail at the moment - if someone has actual proof I’d love to see it), secondly it’s super easy to change an algorithm to make it non-solvable again - keeping the automatic solutions at bay long enough to build another algorithm and so on. Lastly, there are very few people with the sophistication and know how to develop and use these tools as a percentage of the people who spam.

However, none of this issues deter a human CAPTCHA solver. If you remember my last article on this, we were seeing the economics drop significantly to where this is suddenly worthwhile, and if you read the comments of that post even more of these CAPTCHA breaking crews are popping up all over the world. Why wouldn’t they? Someone is willing to pay for it, so why wouldn’t you, if your family needed food? Sure the money may or may not belong to the spammer, but legit or not, the money is still real enough.

That leads me to something I found on the Internet while I was searching for more information on the economics of it. During my searching, I happened across some job offers for CAPTCHA breakers (also known as data entry). The advertisement was pretty intriguing:

CAPTCHA breaking job offer
Click to enlarge

The way the job offer is written is like it’s a stay at home sales person, or some other sort of semi-professional position. Words per minute, 12 hour shifts, a PayPal account along with an internet connection appear to be the only pre-requisites. I thought it was fascinating. Also, the economics appear to have dropped significantly from the last article I wrote a year ago. Now people are being paid $1/1000 CAPTCHAs solved, rather than five to nine times that, which is pushing this market into different directions due to increased competition. Perhaps there are other additional benefits for using a more expensive Romanian service verses the cheap version the Philippines are offering.

Unfortunately, I haven’t seen the operations personally, so I have to speculate that it’s less about the service and more about the cost of operations in the various countries. If anyone is willing to show me their operation I’d love to see it. In the mean time I think we should think about what exactly CAPTCHAs are offering us, and how we are sponsoring micro-economies in countries based on fraudulent human form filling. Is that really the goal? Is it actually the deterrent we intended? Perhaps we should be looking at other/better options.

Phishme.com Internal Communication

Thursday, March 6th, 2008

Well, I’ve had to sit on this info for quite some time but I’m happy to see that Phishme.com is now up and running. Phishme.com is founded by the Intrepidus Group who you may have heard of, with names like Rohyt Belani and Aaron Higbee at the corporate head. What is it? It’s education, but the kind of education that actually works for a change. If you’ve read this site long enough or heard my speeches you probably know I’m not the biggest fan of consumer education. It just isn’t impactful and it doesn’t give enough incentive for people to pay attention and learn. People don’t digest the information and they don’t become armed with the correct information on what to do when faced with an attack. That is until now.

Phishme.com uses a fake phishing attack to simulate what a user might see in a really targeted (Spear-Phishing) attack against the company. Specifically it scrapes the pages of an organization’s website and then sends everyone in the company a phish email to entice them to click on it and give up their credentials. Once the user is phished their information is logged and aggregated for future use by the security team to do further communication with the impacted employees or build further metrics, etc. Screenshot of the interface:


Click to enlarge

Does it work? Preliminary numbers in at least one exercise with 24,000 people say there is a huge drop in the numbers of users who stop clicking on links. In the first run of one experiment 82% opened the email and 64% entered info. In the second 28% opened and 27% entered info and in the third 4.5% opened and 4% entered data. That’s a pretty impressive reduction because it’s actually actionable and it gets people thinking almost immediately about the problem and that it can and will negatively affect them personally. Would you rather phish your users or have the bad guys do it for you? Ethics of owning your own employees aside, I think it’s hugely valuable to know this information.

There are all sorts of legal implications for doing this to your own staff and personally I think those issues are almost completely outweighed by the benefits of solid actionable training. When I talked with Rohyt about this, I get the feeling they’ve spent a lot of time trying to make the interface as difficult as possible to inadvertantly get compromised by trying not to actually transmit the password. So all in all, I think this product is going to do a lot of companies a lot of good. I can think of a dozen or so companies that need to go through this training right now. With phishing attacks becoming a constant and ever present attack, this is a very timely product!

Phishing Using FasterFox Prefetching

Thursday, January 3rd, 2008

I actually had to read this email several times before I got it - paranoia taking over - I thought I was being told my site was hacked. No no, just another interesting way to abuse people that people find when visiting my site. This time, this email comes from Alex who found that pre-fetching can be used to phish users in certain circumstances.

When I’m visiting http://ha.ckers.org/blog/20070608/cross-domain-basic-auth-phishing-tactics/

my Firefox showed up the HTTP-Auth dialog immediately, which I placed on my subdomain testing.bitsploit.de But why I asked myself.

I looked into your HTML source to find a hidden image or something like this, but I didn’t found anything but the link. I haven’t clicked on the link, so why does it pop up ? Than I figured out, that the FasterFox-Extension for Firefox prefetches that link and that’s why the HTTP-Auth dialog pops up.

So there’s another chance to trick FasterFox-users (in forums) without having to use HTML/BBcode for embedding images.

Alex is absolutely right. In fact, this is the exact reason I never used to use Opera (it turns out this is not the same kind of prefetching that Opera does, I only just learned). Sure you can turn it off, but pre-fetching has always been a dangerous thing to me. It can speed things up because it pre-fetches and caches the results, but if it pre-fetches and triggers something, like auto-deletion of your account, or automatically adds something to a shopping cart or anything else, you run into some pretty serious problems. Think CSRF. So yes, this apparently can also be used for phishing in FasterFox. But either way, it’s a very cool example of why pre-fetching can be nasty.

MySpace Anti-Phishing Techniques Need Work

Sunday, November 11th, 2007

I was anonymously sent this link to an article talking about MySpace phishing attacks. The article talks about the newest phishing scam, which essentially just puts username and password fields on user’s profiles, asking for their information. Same old attack, just another day. But this is the part of the article that is actually noteworthy. The MySpace CSO, Hemanshu Nigam, suggests the following will help you from phishing attacks on their site:

But MySpace’s Nigam offers this advice to prevent phishing scams as well:

* Install the latest operating system and auto-install for critical updates.

* Use a firewall.

* Use anti-virus and anti-spyware software and keep them updated.

Does anyone else see a problem with this? Absolutely none of these will protect you from MySpace phishing attacks. So the CSO of MySpace either doesn’t understand the problem he faces, or he has no idea how to help consumers solve that problem. Either way, it’s scary. There are possible solutions to the problem in the browsers, but those are a long ways off. I’ll be talking about a number of them this week at the World OWASP/WASC conference in San Jose. In the mean-time, ignore the CSO of MySpace’s advice. His advice may help you solve other security issues, but not MySpace phishing attacks, unfortunately.

ThreatSTOP Anti-Botnet DNS

Monday, September 17th, 2007

I was asked to take a look at ThreatSTOP the other day. Although it’s not very clear from the website after signing up I found out the basics. It’s essentially a lot like OpenDNS. In fact, it’s so much like OpenDNS that I actually confused id when I said what it was because he thought that’s what I was talking about. It’s not exactly like OpenDNS - there are a few differences.

First the similarities. They both rely on DNS to protect consumers (not websites) from contacting “bad” sites. They both require that you use their sites to perform the lookups on your behalf. They also share some of the same negatives - bad guys who use IP addresses are unaffected by this mitigation. It’s always reactionary - meaning it won’t block you from going there until it knows it’s bad. And if you’re paranoid, don’t forget that they both get to see every site you intend to contact.

Now for the differences. It appears that OpenDNS has quite a bit of added customization that you can put in front of it - allowing customized blocklists. OpenDNS also uses a block page, which theoretically could see the actual URLs you are going to (since it takes over the DNS for them - rather than simply blocking the request completely). Lastly, and the most import difference between the two: OpenDNS focuses on Phishing and ThreatSTOP focuses on malware infested websites.

Maybe one of the two companies should just buy the other? Not that I use this kind of stuff, but for those who do, it seems like you’d want to be protected from both threats as a consumer, not just one or the other.