Category Archives: Secure things

Secure things

Tweaking My Website Security

WordPress is frequently used for websites and therefore attractive to some unfriendly people. So I reconfigured my WordPress security plugin.
And the mails of failed logins started coming in. It was not me, so someone else wanted to use this web site.

A short history about my tooling

For me web site security is something to review on a regular basis. It all started with an article in a magazine.  I put some elementary stuff in place: limited number of log ins and removed the login from the web site.

Over the months I added extra stuff like SSL. It encrypts the traffic between the browser and my web site. In other words my user name and password are unreadable for interested bad guys
Troy Hunt mentioned SSL in his free web course with the haunting name: Hack Yourself First.  Cheers mate.
In case you missed it SSL can be obtained for free at Let’s Encrypt.

At a regular basis I updated the software for my web site. I thought I was quite good until I changed the settings.

A short note about security

Some people might complain about the default security settings of their web site settings. Believe me things can be improved. If you do not set the WordPress settings right, then the user name is shown instead of your writer’s name on the blog post. Luckily there are plugins. (As a Dutchman I could not ignore the free ones.)

I thought about the default security and try to explain to you. If I buy a house, it has standard locks. If I want to keep the baddies out, I have to use the keys.
There are no special keys and locks involved. In case I need them I have to change them.
My new house has no vault or armed guards. If I need them, then I have to change something.

Shorten my list of security mails

So I had changed something and security mails came into my mail box. I noticed that there were mails with wrong user names and passwords. Not good.

After a few days I expected them to stop. You know: “Oops wrong web site. Sorry for that.” But the flow of failed login attempts did not stop. So I had to change something. Again.

I remembered a firewall in one of my WordPress plugins, so I had my first taste of a firewall. Dry, not shaken.
I had IP addresses of the sources of attack. Courtesy service of one of my WordPress iplugins.
An IP address consists of 4 numbers separated by a dot (.) like the invalid 345 345.345 345.

So I put the most offending IP addresses on the black list.

Three strikes and you are out.

The brute force attacks continued. The following combinations were used:

table with failed login attempts

The  user name is in the heading and the password is  shown in the first column. More details about this teaser will be added in the appendix.

My action did not change the flow. I used the asterix. 345 345.345.*. All people coming from IP addresses starting with 345.345.345 got blocked.

Wrong zone. Offsite. Stop the game.

It looked like I had put oil on fire. My normal mails were somewhere between the security mails.

I also noticed that black listed IP addresses still passed through. So there were apperently some smart guys pick locking the door of my web site. I’ll add some words to this assumption  at the end.

It was time for harsh measures. I was so focused on the mails, that I skipped my notetaking. In my logs other URLs were mentioned.  I clicked on one containing wp-admin and noticed that I saw my login page.
I changed a name somewhere and the security mails did not come in any more. Phew.

Brief briefing about red teaming

My list of WordPress plugins would be quite interesting for the people who really want to block out the intruders. The main reason I do not list them is red teaming. This military term is like give my plan to the red team, who will misuse this knowledge to my full disadvantage. Did you notice that “full” sounds like “fool”?

My steps for red teaming of my web site:

  1. Install the web site with all plugins.
  2. Configure the web site and the plugins.
  3. Look at www.cvedetails.com for any bugs.
  4. Misuse the listed CVE or Common Vulnearbilites  and Exposures.
  5. Go to the subdirectories and look for strange files.
  6. Look whether those files are accessible from the outside.

This reads like the plot of a bad B movie. But it works.

A short note about security

Some people might complain about their default website settings. Believe me things can be improved. If you do not set the WordPress settings right, then the user name is shown instead of your writer’s name on the blog post. Luckily there are plugin.

I thought about the default security and try to explain it to you. If I buy a house, it has standard locks. If I want to keep the baddies out, I have to use the keys.
There are no special keys and locks involved. In case I need them I have to change them.
My new house has no vault or armed guards. If I need them, then I have to change something.

Had a short glance

The days after the intentional reduction of my mail I had another look to my log files. My login page was requested several thousands times in a month. And I can assure you that I was not blogging so much.

There were other pages or URLs which led to my login page. So a check on the hits on my login page would give me the wrong impression of safety. There are people who do not like to use numbers or metrics. Some numbers can be really useful when pondered upon.

Somehow I had not paid attention. Too much focus on blogging. Obviously.

An article of Santosh Tuppad was quite helpful to increase the security. Thanks mate.

I even noticed that wp-content was open. So any pictures of draft blog posts could be viewed before publication. I even discovered a CSS file of a WordPress security plugin, which I could access without logging in. It was like finding a business card of a security team at the doorstep.

Wait a moment.

Let’s turn this into a multiple choice question.
What is the reaction of thieves on the business card?
A. Let’s skip this house.
B. I know how these guys operate. Piece of cake.
C. Look at the big bird and the shield of armor. That is pretty neat. We need 500 of those cards.

Definitely something for an action movie.

Some tips:

  • Read the reviews of the WordPress plugins.
  • Install WordPress plugins from the official site.
  • Write down, what works.
    Some plugins do not mix. This might be the cause of the strange behaviour of my firewall.
  • Make an offline copy of the website before tweaking.
  • Tweak the website security several times a year.
  • Go to your web site on a regular basis and install the updates.
  • Keep on an eye on Social Media.
    Troy and Santosh are great sources.
  • Basically, explore your web site security.

Appendix A bit of data crunching

For my first real life forensic investigation I wanted to use the gathered data. As in Data the Gathering. In order to process my e-mails I used baregrep, vim, Javascript, CSS, HTML.

People had attempted to break in my web site. I expected a concentrated set of failed attempts like
expected heat map

When I looked to the patterns I noticed this:
observed heat map
This is an example of a Blink Test. Lots of info processed in milliseconds and still getting useful info.

Facts:

  • Combinations were entered once.
  • Combinations where user name was the same as the password were frequently used.
  • The same for combination with user name equal to admin

Conclusions:

  • There is a high chance that a group tried to break in. There is a moderate chance that there were more groups which used different lists.
  • A popular user name is admin. See the first column.
  • Single words are favourite, followed by words and numbers.
  • Some user names and passwords were linked to my blog.
  • My blog posts are read.
Secure things, Teach things

daD Talk

One of the things I wanted to develop is critical thinking. Not only by myself, but also by my kids themselves. The led to a rather unpleasant start of one of those dad kid conversations.

There was no way back: a subject I tried to delay for a few years:
computer security.

The complaint about a program was packaged as a request:
“I want to have a computer, which can execute [dangerous module] programs without using [dangerous module].”

I exhaled. My kid had absorbed the information and realised that the use could have a severe consequence for the computer. No more computer time. On the other hand the disadvantages were too big to forget about it.

I tried to find a solution, but I could not find one. If a program can change things on a computer, then it can do bad things.

While blogging I realised I was wrong. There was a work around.
There are programs, which can do same things like the original program, but they are built differently. They are called emulators. Some gamers like to play low resolution games on emulators of very old operating systems.
Wow, that’s my kid.

It’s hammer time

“If you have a hammer, then you can use it to break a window. But that’s not right.”
My kid nodded.
“So I program the hammer, so it cannot be used for a window glass. Then I can go to a door and use it to break a lock. I can program it not to break a lock. Then I can use it for a window frame.”

It would be easier to tell the hammer it could only be used on wood. This looks brown and it has grains. But it could be changed, so that everything looks like wood.”
I made a wide gesture with my arm pointing to different objects in the room.

“But I could change the picture. All objects would look like wood. That is not a good idea, so I store the picture in a book. But the picture in the book can still be changed.

Then I could place a lock on it. But the lock could be picked. I could place a better lock on it, but then the whole book could be replaced by another book.

And that’s why it is so difficult to secure things.”

Another unpleasant guest
My kid had seen a cool app. And it should be installed absolutely. So I did my dad thing:  looking at the permissions, which I would grant to the app. It could handle my files. It was just a game and why should game have a peek at my files? Time for the bad news.

So I told my kid, that the app would access files on the phone. The reply was to buy a phone just for games. Then I told that after a while the phone would be also used for other purposes like making pictures. “You don’t want your pictures in someone else’s hands.” There was a lack of nod.

I needed another way to tell the warning. A visual one.
“Suppose someone comes in. He looks television for the whole evening. And he eats the whole fridge empty.

If you protest, he will say:
“You said I could come in.”

The next evening he comes back. He takes the table and the sofa out of the house.

If you protest, he will say:
“You said I could come in.”
“

Secure things

Security by Luck

Last week I saw the attack vectors of the most popular attack on
WordPress web sites at the moment.
Just two lines.

Was I prepared? Yep.

In my mail box I had a message, that my web site was updated. It was completely automatic.

I did not even have to press a button. Self service is nice, good service is better. I had the last version of WordPress running. All minor updates are automatically deployed.

Why did I choose WordPress? For one of my test assignments I had to test a WordPress web site. And I did not want to learn another tool to maintain a web site. Sheer luck.

Last year I got an insistent mail from my host provider, that I should upgrade my PHP. The advised version was a safer one.

I dutifully followed the instructions: pressing buttons instead of typing long commands after the prompt. There was nothing scary about.

How did I select my web site host?
I looked for a provider, who provided all kinds of handy services: e-mail, backup, and web site statistics.

“Sheer luck mate. “
“Really? “
“I compared several providers. The one I chose also focused on companies. If I ever would scale up, I had a company, who could help me. “

“Can you be more specific? “

“Sure. I looked for the information on the web site. It was written in a way that I could advise it to a company.

It had also enough tech background information. That was good for my inner nerd. “

“Wait a minute. “
“Yep. “
“You just told, which Content Management System you use for your web site. And that you are using PHP. Are you not exposing too much information? “

“A real hacker can determine this information within seconds. He looks at the source code or using some plug ins.
On my smartphone I have Dual HTML Viewer which is a similar tool.”
“How did you find that mobile tool? “
“#30daysoftesting

You could call it luck. I prefer to bend it.“

No comments please

Seth Godin once gave the advise to turn off comments in a web site. If the blog post would be interesting enough, then they had to refer to it. Free publicity.

This time saver was a nice advice for me. Yes, I like good comments. Sorry, I focus on writing.

This year I started to test on XSS or Cross Site Scripting attacks. I basically added information to a web site, which changed the behaviour.

If I add html code to a comment, then the comment can be shown in bold or italic. Sometimes it is possible to add extra feature like a window. This can be used to distribute confidential information to other people. Without their permission.

No comment disabled the use of XSS. Luck? Not really.
Seth let me think in another way.

BTW Seth did advise to use comments in the very same blog post.
It is nice to read good things about my blog posts. But for me time is (my) precious.

Don’t be too infectious

One of the criteria to choose my own web site host was full control over the content of my blog. Even I had to pay for it.

There are web sites which provide free web sites, SSL and nice domain names. Their business model or their way to earn money is advertisements on my web site. Of course I can disable it by paying.

On a security conference a Finnish guy showed how advertisements can be misused. He contacted to a web page with a single bad pixel. His system was contaminated within milliseconds. Life on stage.

Reading the right stuff

During one of my visits I saw a familiar computer magazine on the table: “I read it also.”
“It is good.”, was the answer. He also works in the IT, so I valued his input.

Once I read about WordPress tools. There are a lot which are free. So I scheduled my backup and restricted the access with a special tool kit. Sometimes I feel lucky to find easy to use tools.

A Case of Bad Luck
Within two days after pushing my first piece of this blog post on the web I found two annoying items on the web.

Santosh Tuppad had considerable considerations about the use of WordPress by hospitals. And Santosh is a good security tester.

Kristine Corbus, another tester, blogged about the misuse of headers in WordPress.

Then I had a story of Troy Hunt lingering in my memory. He used another Software as a Service for his web site.

“You wrote Troy.”
“It is not a city in ancient Greece, which had the first bad encounter with a Trojan horse.”
“Who’s Troy?”
“It’s the guy who reported about the bleeding cloud and the eavesdropping teddy bears. Troy is a security expert I follow by luck.”

Was I lucky?