On November 22, 2014 while removing malware from a number of sites, we noticed a large number of them had backdoor shells buried in the revslider folder. After the first 100+ sites, we noticed the pattern.
A little Google searching found this site: http://whatisgon.wordpress.com/2014/11/30/another-revslider-vulnerability/
Our first notification was to hosting providers we work with. We told them what to search for so they could alert their customers. The problem was that we did not report it to the right people. That was our mistake.
The first sites did not have any code injected into the swfobject.js or collect.js files, or the .html or .php files. The sites simply had numerous backdoor shells spread throughout the wp-includes, wp-admin and wp-content folders. It appears as if the hackers were looking for the deepest level folders they could find.
Some online searching showed very few infected sites. 1,100 sites. We did reach out to those website owners to let them know – not to try and drum up business but to be responsible. And discrete.
Many of the forums are reporting links to
122.155... but we’re also seeing links to other IP addresses as well. The injected malscript can be in just the swfobject.js files or all .js files, all .html and selected .php files.
Some of the sites have code injected into the collect.js file which apparently is the same code that the malicious links point to. This leads us to believe that the hackers could use these infected sites in their future malicious links and most recently we see the infectious code using the local sites URL pointing to the infected collect.js file.
You’ll find the malicious code in the template-loader.php file located in wp-includes folder. This should be replaced with a copy of the original file downloaded directly from the WordPress site.
Our searches showed a growing number of sites being infected. As of December 17, 2014, we saw 307,000 sites still infected with this – and they have all been verified by us as well.
We did not want to be the one to let every script-kiddie know so they could go out searching for these sites and take advantage of the backdoor shell on all these sites. We’ve been contacting these site owners to let them know and we feel that is the responsible thing to do.
I’m not saying that this was reported wrong. I’m just saying we made the decision to not report it to the masses.
Maybe a missed opportunity. It’s not the first time and it won’t be the last.