WordPress is the most popular Content Management System in the world, and a significant percentage of the sites on the Internet use it. That popularity is well-deserved, but it also makes WordPress an irresistible target for hackers who want to spread malware.
How to Tell if Your Site’s been Hacked
Sometimes it is obvious that your site has been hacked. Occasionally hackers will simply redirect the site to a different server, so that visitors to your domain end up at a site infected by malware, a site displaying advertising the hacker can profit from, or a porn site. But often hackers add malware or spam links to a site which they want to remain undetected for as long as possible. Having a hacked site can infect your visitors with malware, and it will almost certainly result in a huge hit to your SERP rankings, or even blocking by search engines, so it’s important to be vigilant. There are a number of tools available to webmasters to determine whether a site is vulnerable and whether it has been hacked.
The WP Security Scan extension won’t tell you whether your site has been hacked, but it will check for possible attack vectors and vulnerabilities, and offer suggestions for fixes. Of course, often the vulnerabilities will not be in WordPress itself, but in some other part of the software stack. The best way to ensure that there are no known exploits that hackers can use is to keep your software as up-to-date as possible.
Google’s Safe Browsing Diagnostic
Google has a service that enables webmasters to see whether they consider a site to be dangerous to visit. Copy the following URL into your browser address bar and replace the part following ‘?site=’ with your site’s URL.
Sucuri offers a free site scanning service that will catch major problems, and a paid for monitoring and cleanup service that can help if you are hacked.
Using these tools together can help you ensure that your site remains safe.
What Should You do If You’ve Been Hacked
Unless you are an experienced and expert developer or website administrator, cleaning a site with any level of confidence by yourself is almost impossible. Even if you think you have found all the malicious files and removed all the spam links, the files that make up WordPress itself may have been altered so that they reinfect a site after an attempted cleanup.
Contact your hosting provider and let them know you’ve been hacked. You might not be the only victim and the host provider’s sysadmins may already be taking action.
Securi, as mentioned above is an excellent tool, and it will attempt to auto-clean your WordPress installation. Should you choose not to use Securi, or hire a professional to clean your site, then the next best option is to delete the site and restore it from backups.
Hopefully, your site is hosted with a provider that offers a comprehensive backup service, in which case restoring the site to a previous version should be very simple. If not, we are going to assume that you have been making regular backups of your WordPress database.
Download a fresh install file from WordPress.org, to replace any files that may have been altered during the attack. Do not use the same passwords on the new install as you used on the hacked site.
After you have installed a fresh version of WordPress you can restore the WordPress database from a backup that you know to be clean.
Since you know that your site has been hacked once, and that there were vulnerabilities that malicious parties were able to exploit, if possible, it may be best to completely reinstall the server and restore from backups. At the least very scan the server with an anti-malware tool. If you are reasonably sure that the infection was limited to WordPress, then you should update all of your software to the most recent versions, to close vulnerabilities. If you’re using shared hosting your provider should take care of this for you.
If you haven’t been taking database backups, it may be possible that the WordPress database has not been breached, and that a fresh install of WordPress using the existing database is enough, but in that case be extra vigilant of alterations, follow the rest of the above advice, and start taking regular backups!