Archive for February, 2016
At this point we’ve got a good MySQL dump of the compromised WordPress site. Now what?
To the cloud!
As I alluded to in the earlier parts, I’m going to load the MySQL dump from the ancient (compromised) site, then re-dump it out as WXR (WordPress backup) so that I can import the whole thing into WordPress.com.
I’ve got the database dump, now I need a WordPress instance to load it into.
In the olden days, I would have grabbed some hardware, loaded Linux, then mySQL, then Apache, then WordPress. I only need this for a few hours, so why spend a half day doing the basic installation? It turns out there’s a great alternative.
Bitnami has a pre-configured LAMP+WordPress image available from the Amazon Marketplace. I can use their image for only US$0.13/hour on a c1.medium AWS instance. or US$0.02/hour on a t1.tiny instance. I figure I need at least two-three hours of run time, and I don’t want to run into any size/space limitations of the t1.tiny instance. So I’ll gamble and use the c1.medium. That means I might spend up to a little over US$0.50 (c1.medium) if I need 4 hours instead of only US$0.08 for 4 hours if I use the t1.tiny. I’ll take that gamble 🙂
1. Spin up a WordPress instance using the Bitnami image
This was pretty easy. Just start from the Bitnami pre-configured image in the Marketplace, and then proceed to the launch area. You’ll see that there’s a m1.small instance type already selected. This is where you can decide to use a c1.medium, or take the m1.small default. Just proceed and spin up the instance. Then proceed to the AWS Console to get the DNS hostname.
2. Configure WordPress on the instance
At the bottom of the AWS console you’ll see a section labelled “AWS Marketplace Usage Instructions”. This will lead you to the username and the password (which will be in the instance’s boot log file). From there you can log into the WordPress instance over SSH with the username “bitnami” and your AWS private key.
3. Load and check the database
Log into the WordPress instance and use the control panel to load your MySQL dump into WordPress. Switch to the site view, and start scrolling through the blog posts and other links.
In my case, I found about a dozen posts that were still broken. This sent me back to the raw database edit (see Part 2) to re-edit the database text file dump. I edited out the broken records, re-dumped the database, and started again at step 1 above.
Once you have a valid WordPress site in your AWS instance, it’s time to get that WXR file we need for the import into WordPress.com.
4. Export the valid WordPress blog
Jump into the WordPress control panel, and use “Tools -> Export” to create a WXR file and download it to your computer. Once you’ve done this, you can spin down the AWS instance using the AWS console. Use “Terminate” so the EBS volume will be released as well.
We’re almost done. Next time, creating and loading the site into WordPress.com.
Let’s get started recovering the site. See Part 1 for the background. Note that I actually did this recovery in February 2015, and some software may have changed since then.
1. Dump the DB of the infected site in the test SQL dump format. This creates a human readable (and editable) file on my laptop.
There are all kinds of tutorials out there on dumping a SQL DB using phpMyAdmin. They are all better than I could write. This one, for example.
2. Examine and edit the DB dump file to remove any obvious damage. Is it worthwhile to continue?
For this I used Emacs. Yes, Emacs. You can use any test editor that you understand well, that has a “repeat this edit” or a general “search and replace” function. It must handle long lines, as each DB record is on a single loooong line. It helps if the editor can deal with escape characters. To make a long story short, the damage was almost immediately obvious. I was able to find the suspect lines and ^K (kill) them pretty quickly. For large values of “quickly”. There were about 1500 damaged or bogs records. Using search/replace and making a “fine pattern and kill line” worked wonders.
OK, after about 45 minutes of editing, I’ve got a clean database. All the records that I see are (probably) valid WordPress code/values or (probably) valid user records, or image pointers. It’s worthwhile to continue.
However, there’s still some cleanup, and this is a raw mySQL dump. I can’t import this into WordPress.com, yet. For that I need a WXR format dump, and this WordPress version was so old, that WXR isn’t even supported. I need a modern WordPress install somewhere that will accept the old MySQL dump and then allow a WXR export.
3. Install stand-alone WordPress somewhere (but how, and where?)
I’m going to use this new environment to examine the site in a sandboxed environment and get a chance at some forensics and to more completely assess the damage. This will also be the bridge between the raw mySQL dump and the WXR file that I import into WordPress.com later.
I expected that installing a new host and WordPress to take the most time of the entire process. In the olden days I would start with a physical host, do a full Linux install, add mySQL, Apache, etc and eventually WordPress. I don’t want to take this much time.
What’s the fastest, easiest way to get a full-blown WordPress setup? Turns out, the cloud is a pretty good place to start.
This series is about how I recovered a compromised three+ year old WordPress site, from a medium/bad compromise with no backups. Using Bitnami’s WordPress package and AWS saved me countless hours and I got all the data back. It cost me a few hours of my time and $0.50 of AWS EC2 usage.
Part I – the plan
Recovering a compromised WordPress site can be either very easy, or very difficult depending on the version of WordPress that you have installed, and the severity of the compromise. At the easy end of the spectrum is recent WordPress and good backups. At the harder end is very old versions of WordPress, no recent backups and a site at a shared hosting provider (no shell access).
This particular site was for a class reunion from several years ago. It was left running because it was hosting some pictures from the event, but was rarely visited. Based on PHP file modification dates, the site was compromised in November, and probably again in December, using two different WP plug-ins. This left behind lots and lots of modified PHP code. There were multiple kinds of PHP damage, which looks like it was done by two different attackers.
In other words, a mess.
Using PhpMyAdmin, I was able to determine that in general the database was touched very lightly, if at all. But the PHP code was unrecoverable. The best plan was to pick the site up and move it to WordPress.com, and abandon the old site (and hosting provider). I decided to pick up the site and move it to WordPress.com so that I wouldn’t have to deal with WP software updates and incompatible plug-ins. Also, the managed hosting company had bumped its rates from around $50/year to over $150/year in the 9 years the site has been running.
But WordPress.com only accepts a WordPress Export File (WXR) as the import source. While stand-alone installs of WP offer many import options, WXR is the only option for WP.com without engaging their $ervices. This broken WordPress was old enough that it didn’t even offer the WXR as an export option. And, I wasn’t sure that I wanted to import the site wholesale until I had a chance to examine it.
This was my plan.
- Dump the DB of the infected site in the test SQL dump format. This creates a human readable (and editable) file on my laptop.
- Examine and edit the DB dump file to remove any obvious damage. Is it worthwhile to continue?
- Install stand-alone WP somewhere. I could use this to examine the site in a sandboxed environment and get a chance at some forensics and to more completely assess the damage. I expected installing a new host and WordPress to take the most time of the entire process.
- Import the database ONLY into the sandbox WP install.
- Test the sandbox WP site to see if there are any remaining landmines.
- Decide if it is still worthwhile to continue.
- If there are repairable problems, fix them in the original DB dump file (on the laptop) and clear the sandbox DB.
- Lather, rinse, repeat until the site looks OK
- When the sandbox site looks OK – save it as a WXR file
- Import WXR file into WP.com
- Test site.
- Drink beer.