Phishing sounds similar to fishing. Fishes are to the volume of internet users today much like fishermen are to phishers. Zillions of fishes falling prey the nets is nothing less compared to internet users being phished through their own in boxes and messengers. Phishers tend to have some personal favorites – personal information, credit cards numbers, debit cards numbers with ATM pins, etc. Though phishing has been around for a long time, it became more prominent back in 2003. You can read more here on the big scams here.
How does it all work?
A typical modus operandi:
1) The Phisher would either go out and buy a phishing kit from the underground channels or create a look alike page himself.
2) He would then need hacked websites or a server where the pages can be hosted. This can also be easily made available. He would pay or trade for a list of hacked websites on IRC channels, underground forums etc. These are some very common sources for such deals. He could also target systems that are vulnerable to a particular vulnerability or weakness in the website – vulnerability in the hosting providers control panel software, exploit for popular CMS like Joomla, 0day vulnerability in web server, etc. A zero-day (or zero-hour) attack or threat is a computer threat that tries to exploit computer application vulnerabilities that are unknown to others, undisclosed to the software vendor, or for which no security fix is available. (ref : http://en.wikipedia.org/wiki/Zero_day_vulnerability)
3) Once the hacked infrastructure is ready it’s time to spam. They would ideally send out emails in large volumes. These emails are crafted to perfection. They would have the company logo, an appealing message in the email; use the CSS as the company that is phished, etc. All this together make it look perfect. It’s like decorating the devils face with cosmetics to make it look innocent. But not to forget the devil under a thin layer of cosmetics. They will have a crafted link and the hyperlink actually pointing to some website where the pages are hosted.
However, the entire process is a gamble. Some may fall prey to their phish nets while others may not. Over the years, phishing scams have grown from simply stealing accounts into much more dangerous criminal intention. Assuming the user is a prey of the phish net, let us understand the ways in which a phisher can harvest the data of the victim. There are various ways in which this can be done.
1) The attacker here uses services of websites that let you send HTML forms embedded in your email. On submit of this HTML form the phished page will redirect you to the legitimate website. This often tricks the user. They don’t realize what just happened. The details entered on the form are then emailed to the phisher’s inbox that is supposed to collect the details. The most common examples where you can see them are when advertising on the internet.
2) Second, the email is scripted in a way that a user is tempted or forced to visit the copied website. The attacker can also use the tactic mentioned above and use services like www.emailmeform.com. Attacker creates an account here and links his entire phished page to use their service to capture the details and then email it to them. This is the most common method used by phishers. Also the pages are scripted in server side programming languages like PHP, .NET, JSP etc. Doing so it does not expose the modus operandi or the attacker’s identity in any way or other details in any way.
3) The third type is where the phishers use nothing like above and instead writes all the output to a predefined file. In this way he needs no email address or anything mentioned above to capture the user details. This is what I am exactly going to write about.
Since I had some time off before I could start with the next takedown, I decided to dig further. Before we begin let me give you a brief about our service and the client. We offer take down services to a large public sector bank. We have a strict timeline defined of 24 hrs for every takedown. Every time a customer or their monitoring reports a phished page we have to takedown the site to protect the loss of financial and other details. While doing takedowns I also get a chance to research on understanding the modus operandi behind the operation. It is very interesting.
I have just started my day checking my email over a cup of coffee. I receive a new email on Tue 11/3/2009 10:22 AM about a phished link being up with the URL and we need to immediately start the takedown. He also sends me a sample email. We did the usual process and the link was down by noon. Have a look at a sample phishing email.
The email looks so real. It has the logo of the customer and perfect login URL. On hover I found it was actually pointing to some server in Russia. The page ‘retails.html’ simply redirects to the next URL where the phished page is hosted. Have a look at the closing lines of the email below. The phisher uses pressure tactic that will force the user to browse the URL.
Ok I now click and I am now redirected to the URL http://200.119.X.X/retail/login.php. The page looks like this
I then enter some fake details on this page and press the Enter key. I am now redirected to another page called ‘accounts.php’ on the same domain. I quickly check the html source code (view source) of the page to check for the