As you probably know WordPress sites are constantly under attack from all over the world regardless of where your site is hosted or what kind of site it is. Ever since I first noticed suspicious traffic on my own WordPress site many years ago I’ve found it fascinating to watch.
To satisfy some of that curiosity I decided to write a script that collects data on failed logins. I activated it early last year and it’s since then been collecting username, password and a few other things for all login attempts that were not made by a user on my site.
This isn’t a very large dataset of course but I think the results are still worth sharing because they give an indication of some patterns in brute force attacks on any single WordPress site. Please note that I’ve only recorded data from logins made to wp-login.php. xmlrpc.php is blocked on my site. If it’s not blocked on yours it’s good to know that just as many login attempts happen via that endpoint.
Frequency of login attempts
The total number of recorded login attempts on my site during a one year period was 8801. That’s around 24 per day. They do not happen everyday though. Some days it’s completely quiet. Other days there is a barrage. The most active day was May 4th 2018 with 832 logins.
So what does that mean for a WordPress website owner? It simply means that you should expect an ebb and flow and that having 500 or a 1000 login attempts per day is business as usual. Similarly having 0 login attempts one day is normal as well.
The number of unique IPs was 820. That gives an average of 10 attempts per IP but the average is misleading here as well. If we look at the distribution of attempts per IP we see that most IPs only make a few attempts. 672 IPs (82%) of IPs made 3 or less attempts.
See that flat distribution around 100 logins? It means we have a lot of IPs that are making ~100 attempts. I think it’s safe to assume that’s either all the same person or the same exploit kit, perhaps by default configured to make 100 attempts against each site. Consider also that IPs with few attempts are likely part of a distributed attack where requests may come from the same threat actor but with different IPs each time. This is known as a botnet.
Most common usernames and passwords
What do you think was the most common username in the login attempts? I have a feeling most people would guess “admin”. Close! That’s the second most common. The most common one is the domain name stripped of it’s top domain.
The chart above shows all usernames in the data. I was expecting to see more variation. The curious one is Åsa. That’s my first name! I’m guessing it was scraped from my website, perhaps from the title.
Passwords are a bit more interesting. There are 490 passwords that were used in the 8801 login attempts. My first name appears here again with passwords such as Åsa0, Åsa2 and Åsa123. Those were only attempted a few times though. The most common passwords by far were variants of the domain name minus top domain plus a few numbers (commonly a year such as 2005, 2010 or 2017). “123” takes second place as the most commonly occurring string and “admin” lands on third place. Let’s also give a honorary mention to passw0rd, secret, hunter and qwerty.
Summarizing now the takeaway would be something like this
- It’s normal to have large amount of malicious login attempts on a WordPress website. If you install a security plugin and see lots of login attempts – don’t freak out. Those logins were always happening but you just didn’t see them before.
- Login attempts in large numbers aka “brute force attacks” are generally predictable. There is very little variation in the usernames and the majority of passwords follow a common pattern.
- Don’t use your domain name in your username or password. Also don’t use “admin” but hopefully you already knew this.
- Be aware that your website can be scraped and that the data can used against you. It’s not common, but some bots are smarter than others.
Remember that this is a small dataset from one website with it’s own peculiarities. I block all xmlrpc.php requests. I’ve hidden my actual username. If you have a theme that exposes your WordPress username, or if you haven’t blocked username enumeration you’ll likely see a lot of login attempts with your actual username.
I’ll end with a word of caution of another kind. If this post inspired you to start logging things that’s great but be careful. You don’t want to accidentally log actual users passwords or any other private information.
That’s all for today. Happy coding! Have fun!