Breaking Apart a Phishing Attempt

in technology •  6 years ago 

Some time ago I received a suspicious email that claimed I was due in court for some legal obligation. Knowing that the American legal system doesn't contact you by email, I was curious. This was interesting, since the only kind of spam I ever received was for fake sunglasses or payday loans. What really caught my eye was the attachment, Court_Notification.zip. I pulled out an old laptop I use for this sort of thing and went to my local Starbucks.

Once verified that it was in fact a .zip, I opened it up. It contained one file: Court_Notification.doc.js. This was a huge relief, for two reasons. The first being that the malicious code was delivered overtly, making it a lot easier for me to focus on what was important. The second was that it was written in JavaScript, a language I was far more comfortable with than say, C++. Below you will find a Github Gist containing the unedited JavaScript. Please don't do anything stupid with it. This is for educational purposes only.

https://gist.github.com/ChrisGermano/ff651183be0ca1bf81cd7012ab89dd19

While the code looks pretty messy and repetitive, it got me thinking. Every function had pretty much the same structure, except one.

var __port__in = '';

function __viewer__desk__src__ca(_v_) {
    __port__in = __port__in + _v_;
};

Ultimately, this chunk of JavaScript is concatenating a string from a garbled mess of functions and hard-coded parameters. While I could, and should, have automated the process, I crawled through the code by hand. In the first four __viewer__desk__src__ca() calls, __port__in already contains eval. Now the end goal of the program was pretty clear. The final code evaluated to the following (and same as above, educational purposes only):

https://gist.github.com/ChrisGermano/3b25b82ce7ade6f9aed712fc7d08c5eb

So what's interesting about this? The three hardcoded URLs point to an American Muslim blog, a mask store, and a bookkeeping service owned by a property management group in Florida. From a brief investigation, the three sites have nothing in common in terms of content or ownership, so it's likely motivated by a technological vulnerability rather than a political or personal attack.

I went back to the original email and noticed the sender's address wasn't from a domain that had anything in common with the websites in the second script. [email protected] came from a Brazilian furniture store that, when navigated to, directs you to an admin login panel. If you don't log in, the website loads normally. There was also no mention of a Calvin Farris anywhere on the site or associated business pages.

At this point, I was pretty sure I knew what was going on, and I'm confident my hunch was correct: this is an attack on sites using outdated versions of Wordpress. While it may not be the most exciting conclusion, I found all of the sites in the script, as well as the likely compromised Gavelar, were using early Wordpress 3.x.

Do any Wordpress experts have more insight into the low-level functionality of the second script? Have you received a similar email? Comments and votes are greatly appreciated, and thanks for reading!

Authors get paid when people like you upvote their post.
If you enjoyed what you read here, create your account today and start earning FREE STEEM!