This guide is created specifically for a type of hack that adds keyword-heavy gibberish pages to your site which we’ll refer to as the cloaked keywords and links hack. It’s designed for users of popular Content Management Systems (CMSs), but you’ll find this guide useful even if you don’t use a CMS.
Note: Unsure whether or not your site is hacked? Start by reading our how to check if your site is hacked guide.
Table of contents
- Step 1: Identifying this type of hack
- Step 2: Fixing the hack
- Step 3: Additional resources
- FAQs for Hacked Sites
Identifying this type of hack
The cloaked keywords and link hack automatically creates many pages with non-sensical text, links, and images. These pages sometimes contain basic template elements from the original site, so at first glance, the pages might look like normal parts of your site until you read the content.
The hacked pages are created to manipulate Google’s ranking factors. Hackers will often attempt to monetize this by selling the links on the hacked pages to different 3rd parties. Often the hacked pages will also redirect visitors to an unrelated page, like a porn site where hackers can earn money.
To check for this issue, start with the
Security Issues tool in
Search Console to see if Google has
discovered any examples of these hacked pages on your site. Sometimes you can also uncover pages
like this by opening a Google Search window and typing in
site:[your site]. This
will show you the pages that Google has indexed for your site, including the hacked pages. Look
through a couple of pages of search results to see if you spot any unusual URLs. If you don’t
see any hacked content in Google Search, try the same search terms with a different search
engine. Other search engines might show hacked content that Google has removed from the index.
An example of what that would look like is below.
Note: Notice that the search results here contain many pages not created by the site owner. If you look closely at the descriptions of second and third search results descriptions, you’ll see examples of the gibberish text that this hack creates.
When you visit a hacked page, you might see a message suggesting that the page does not exist (for example, a 404 error). Don’t be fooled! Hackers will try to trick you into thinking your site is fixed by making you believe the hacked pages are gone or fixed. They do this by cloaking content. Check for cloaking by entering your site’s URLs in the Fetch as Google tool. The Fetch as Google tool allows you to see the underlying hidden content. Below is an example of what these hacked pages look like.
Fixing the hack
Before you start, make an offline copy of any files before you remove them, in case you need to restore them later. Better yet, back up your entire site before you start the cleanup process. You can do this by saving all the files that are on your server to a location off your server or searching for the best backup options for your particular CMS.
Check your .htaccess file (3 steps)
The cloaked keywords and link hack uses your .htaccess file to automatically create cloaked pages on your site. Familiarizing yourself with .htaccess basics on the official Apache site can help you understand better how the hack is affecting your site, but it isn’t required.
Locate your .htaccess file on your site. If you’re not sure where to find it and you’re using a CMS like WordPress, Joomla, or Drupal, search for ".htaccess file location" in a search engine along with the name of your CMS. Depending on your site, you might see multiple .htaccess files. Make a list of all of .htaccess file locations.
Note: The .htaccess is often a "hidden file." Make sure to enable showing hidden files when you’re searching for it.
Open the .htaccess file to view the contents in the file. In the file, you should be able to identify one line of code that looks something like the following:
RewriteRule (.*cj2fa.*|^tobeornottobe$) /injected_file.php?q=$1 [L]
The variables on this line can change. Both "cj2fa" and "tobeornottobe" can be any mix of letters or words. What’s important is to identify the .php that’s referenced in this line.
Write down the .php file mentioned in the .htaccess file. In the example, the .php file is named "injected_file.php", but in reality the name of the .php file won’t be as obvious. It’s usually a random set of innocuous words like "horsekeys.php", "potatolake.php", and so on. There’s a high chance this is a malicious .php file we’ll need to track down and remove later.
Replace all .htaccess files with a clean or default version of the .htaccess file. You can usually find a default version of a .htaccess file by searching for "default .htaccess file" and the name of your CMS. For sites with multiple .htaccess files, find a clean version of each one and perform the replacement.
If no default .htaccess exists and you’ve never configured an .htaccess file on your site, the .htaccess file you find on your site is probably malicious. Save a copy of the .htaccess file(s) offline just in case and delete the .htaccess file from your site.
Finding and removing other malicious files (5 steps)
Identifying malicious files can be tricky and can take several hours. Take your time when checking your files. If you haven’t yet, this is a good time to back up the files on your site. Do a Google search for "back up site" and the name of your CMS to find instructions on how to back up your site.
If you use a CMS, reinstall all the core (default) files that come in the default distribution of your CMS, as well as anything you may have added (such as themes, modules, plugins). This helps ensure that these files are clear of hacked content. You can do a Google search for "reinstall" and your CMS name to find instructions on the reinstallation process. If you have any plugins, modules, extensions, or themes, make sure to reinstall those as well.
Start by looking for the .php file that you identified in the .htaccess file earlier. Depending on how you’re accessing the files on your server, you should have some type of search functionality. Search for the malicious file name. If you find it, first make a backup copy and store it in another location just in case you need to restore it, then delete it from your site.
Look for any other malicious or compromised files left. You might have already removed all malicious files in the previous two steps, but it’s best to work through these next few steps in case there are more files on your site that have been compromised.
Don’t get overwhelmed by thinking that you need to open and look through every PHP file. Start by creating a list of suspicious PHP files that you want to investigate. Here are a few ways to determine which PHP files are suspicious:
- If you’ve already reloaded your CMS files, look only at files that are not part of your default CMS files or folders. This should rule out a large number of PHP files and leave you with a handful of files to look at.
- Sort the files on your site by the date they were last modified. Look for files that were modified within a few months of the time that you first discovered your site was hacked.
- Sort the files on your site by size. Look for any unusually large files.
Once you have a list of suspicious PHP files, check to see if they’re normal or malicious. If you’re unfamiliar with PHP, this process might be more time consuming, so consider brushing up on some of the PHP documentation. But even if you’re completely new to coding, there are some basic patterns that you can look for to identify malicious files.
First, scan through the suspicious files you’ve already identified to look for large blocks of text with a combination of seemingly jumbled letters and numbers. The large block of text is usually preceded by a combination of PHP functions like base64_decode, rot13, eval, strrev, gzinflate. Here is an example of what the block of code might look like. Sometimes all this code will be stuffed into one long line of text, making it look smaller than it actually is.
<!--Hackers try to confuse webmasters by encoding malicious code into blocks of texts. Be wary of unfamiliar code blocks like this.--> base64_decode(strrev("hMXZpRXaslmYhJXZuxWd2BSZ0l2cgknbhByZul2czVmckRWYgknYgM3ajFGd0FGIlJXd0Vn ZgknbhBSbvJnZgUGdpNHIyV3b5BSZyV3YlNHIvRHI0V2Zy9mZgQ3Ju9GRg4SZ0l2cgIXdvlHI4lmZg4WYjBSdvlHIsU2c hVmcnBydvJGblBiZvBCdpJGIhBCZuFGIl1Wa0BCa0l2dgQXdCBiLkJXYoBSZiBibhNGIlR2bjBycphGdgcmbpRXYjNXdmJ2b lRGI5xWZ0Fmb1RncvZmbVBiLn5WauVGcwFGagM3J0FGa3BCZuFGdzJXZk5Wdg8GdgU3b5BicvZGI0xWdjlmZmlGZgQXagU2ah 1GIvRHIzlGa0BSZrlGbgUGZvNGIlRWaoByb0BSZrlGbgMnclt2YhhEIuUGZvNGIlxmYhRWYlJnb1BychByZulGZhJXZ1F3ch 1GIlR2bjBCZlRXYjNXdmJ2bgMXdvl2YpxWYtBiZvBSZjVWawBSYgMXagMXaoRFIskGS"));
Sometimes the code isn’t jumbled and just looks like normal script. If you’re not certain whether or not the code is bad, stop by our Webmaster Help Forums where a group of experienced webmasters can help you look over the files.
Now that you know which files are suspicious, create a backup or a local copy by saving them onto your computer just in case it wasn’t malicious, and delete the suspicious files.
Check to see if your site is clean
Once you’re done getting rid of hacked files, check to see if your hard work paid off. Remember those gibberish pages you identified earlier? Use the Fetch as Google tool on them again to see if they still exist. If they respond as "Not Found" in Fetch as Google, chances are you’re in pretty good shape and you can move on to fixing the vulnerabilities on your site.
How do I prevent getting hacked again?
Fixing vulnerabilities on your site is an essential final step for fixing your site. A recent study done found that 20% of hacked sites get hacked again within 1 day. Knowing exactly how your site was hacked is helpful. Read our top ways websites get hacked by spammers guide to start your investigation. However, if you’re unable to find out how your site was hacked, below is a checklist of things you can do reduce vulnerabilities on your site.
- Update your CMS, plugins, extensions, and modules regularly: Hopefully you’ve already done this step. Many sites get hacked because of the outdated software running on a site. Some CMSs support auto-updating.
- Regularly scan your computer: Use any popular virus scanner to check for viruses or vulnerabilities.
- Regularly change your passwords: Regularly changing the passwords to all your website accounts like your hosting provider, FTP, and CMS can prevent unauthorized access to your site. It’s important to create a strong, unique password for each account.
- Use Two-Factor Authentication (2FA): Consider enabling 2FA on any service that requires you to log in. 2FA makes it harder for hackers to log in even if they successfully steal your password.
- Consider subscribing to a security service to monitor your site: There’s a lot of great services out there that can help you monitor your site for a small fee. Consider registering with them to keep your site safe.
If you’re still having trouble fixing your site, there are a few more resources that might help you.
These tools scan your site and may be able to find problematic content. Other than VirusTotal, Google doesn't run or support them.
Virus Total, Aw-snap.info, Sucuri Site Check, Quttera: These are just some tools that may be able to scan your site for problematic content. Keep in mind that these scanners can’t guarantee that they will identify every type of problematic content.
Here are additional resources from Google that can help you: