Ransomware: Pay up or Die!

Written on Sat, 25 March 2017

It's 5pm on the clock. Finally, you can knock off from your work and get home for a nice dinner prepared by your wife. Gladly, you hopped on your car and drive out of the parking lot.

As you approach the highway, it just struck you that everybody else is getting home too. Thankfully, the traffic is still flowing very smoothly. You drive steadily at 70 Kilometres per hour on the highway.

All of a sudden, your car accelerates to 90 Km/h on its own. You stepped on your brakes but it didn't respond as you had expected it to. You hear the sound of the locks on your door. Your state of confusion is only mixed with your state of panick as you are forced to navigate through the traffic.

Are you held hostage by your car? Did all the warnings of ransomware finally coming to pass? Your infotainment screen couldn't be more wrong: Pay $5 000 to regain control of car; Increase speed to 100Km/h in 4 minutes 36 seconds!

You want to blame yourself for not heeding those warnings, but there is no time for that now. Your life is on the line!

What is ransomware?

Merriam-webster defines ransom as:

a consideration paid or demanded for the release of somone or something from captivity

Ransomware is a type of malware that holds a victim's files, computer system or mobile device ransom, restricting access until a ransom is paid. In most likely cases, things that you hold value.

The biggest myth: I have nothing valuable

Seriously, you have not thought this through. Would you protest if you bought a computer for $1 000 only to be told that you can only use it if you paid $100 to me? Your physical machine has value on its own. I'm quite sure you will use your computer to quite a good extent if your computer cost more than $1 000.

If getting ransomware while you're driving is not enough to get your attention, you're hopeless. As our society gets increasingly connected and us relying more on technology, we best do everything it takes to

Another myth: I have firewall, anti-virus, King Leonidas, and whole of spartan army

There used to be a saying, China built the Great Wall to prevent invaders from entering. So how did its enemies invade China? By walking through the front gate.

Don't expect to rely on all the security measures in place to stop a hacker from planting ransomeware in your organisation. All it takes is a misinformed user in your organisation to accidentally allow a hacker into your network.

Yet Another myth: It's only limited to computers

Oh so you think you can just shut down the computer and never use it again? Seriously, you need to think about your life being in the line.

How about this, you are driving along the road. And suddenly, your brakes stop working, your hear the door locking, and the car just accelerates beyond your comfortable speed. Your in-entertainment screen prompts this: Pay $5 000 to regain control of your car. What are you going to do?

What does ransomware do?

They prevent you from using your computer or enterprise network normally by asking you to do something before you can use it again.

Typically, ransomware:

• prevents you from accessing Windows.
• encrypts files so you can't use them.
• Stop certain apps from running, like your web browser.

What it holds ransom may not be something that is in your computer. In my example of the car ransom, your life is being held as hostage.

Even if you pay the ransom or doing what the ransomware tells you to do, there is no guarantee that it will give access to your computer or file again. Reinfection is also a real possibility, called milking the victim.

How does ransomware gain access?

Many ransomware gain access through misinformed users. There could be websites that disguise themselves as some form of authority, such as legal personnel or professional personnel, to gain users trust to download and run certain programmes on the targeted machine.

Other entries include downloading files from suspicious websites claim to give users certain benefits like free movies, musics, and softwares. Running these infected files will give hackers the backdoor access it needs.

How do I prevent ransomware?

Backup your data, maybe even OS

I am a big advocate of data backup, ever since I have lost so much data in the past.

One of my most popular tool for data backup is Clonezilla. It does hard disk clone. This is a particularly good remedy when the ransomware locks up your entire computer. You start off with cloning a clean slate of your computer, free from any infection. Then periodically, do up more clones. The downside of this method is that each clone usually takes up huge amount of space. But the upside is that, you can store these clones offline, only to dust it off when you need the data again. Offline storage is a very effective method to prevent hackers from deleting backup copies of your data.

The other alternative is to use duplicati for data backups. My most favourite feature is its strong encryption, using AES-256. When encryption, I could store the data in the cloud, such as OneDrive. The footprint of these backups are low, with incremental backup, compression, and deduplication. The easiest part of making this work, is the scheduler. I set the backups once, and forget it.

Keep your antivirus updated

First, if you don't have an antivirus running on your computer, shame on you! Windows 10 comes by default with Windows Defender. If you deliberately turn it off, face palm right now!

Windows Defender is a very decent piece of antivirus. I'm not here to argue what's the best antivirus. I'm here to tell you to at least get protected. The best thing about Windows Defender is that it comes default on Windows 10, and it's free. You have no excuse.

Now, of course, that is not enough. Make sure you keep it updated with the latest virus signatures.

If you're managing an enterprise system, you best get yourself a hardware firewall on your network. You can built your own firewall with Untangle or PFSense. It comes with open source antivirus, clamwin.

Keep everything else on the computer updated

• Keep your Windows 10 updated
• Keep your Ubuntu updated
• Keep your Centos updated
• Keep Microsoft Office suite updated
• Keep Libreoffice update
• Keep Chrome updated
• Keep Firefox updated

Do I need to say more?

Get educated

Seriously, your users need to know that if the screen prompts them to download something because somebody says you need to download it, doesn't mean they should. Don't download anything from anywhere that is not trusted.

What should I do if I'm infected with ransomware?

That's a tough question. If your life is on the line, I guess you are out of options but to pay the ransom fee.

These hackers make a living out of getting paid from these ransoms. By paying these ransoms, you are effectively funding their operations for more ransoms. It goes without saying that we should not be paying, but it may not be the best course of action. When you are dealing with patient's data in a hospital, it could be a matter of life and death.

All these makes prevention all the more important. The more valuable the subject is, the more measure you should have in place to prevent it.

If you are infected by Crilock family of ransomware, there is a lot of hope. FireEye and Fox-IT tool can help you recover your encrypted files.

I have backups, what should I do?

If you have done your backups accordingly and have enough measure to protect the backup, you have a safeguard. The very first thing you should do is the prevent the infection from spreading. Followed by getting rid of possible entries of re-infection, so that when your restoration effort don't get wasted, or worst, backups get ransomed too.

Evidence Evidence Evidence

Written on Sun, 19 March 2017

Evidence! Is evidence all that truly matters?

Science is a wonderful subject that advanced humanity through the ages. Electricity, automobiles, aeroplanes, internet, medicines, satellites, etc... They could be considered the marvel of modern times. Yet, science seems to be at odds with creation, or is it?

A question of authority

At the heart of the conflict is the difference in worldviews. On one hand, there are those who subject to the authority of God, and on the other, those who reject the authority. The ones who reject will instead put man's ideas as the authority of truth.

When we start with the God's word, we start from Genesis 1:1. We know about 6 days of creation, the order of creation, the 7 day cycle of each week. On top of that, we know certain moralities, such as wearing clothes, marriage, and bearing children. Most importantly, we know that Christ already had a plan to step down on Earth in the first book of the Bible.

But what happens when we start with man's ideas? We observe the rejection of what's beyond the natural. We determine that we are the all and end all. Suddenly, we determine our own moralities, such as redefining marriage. We determine our own truths.

All evidence are the same

All scientists draw their conclusions from the same evidence. Evidence does not speak for itself, but interpreted through a belief system.

We see naturalists doing so. When they noticed so many gaps in the evolutionary tree of their worldview, they proposed punctuated equilibrium. How does a creationist interpret this evidence? It is evidence of creation, that every animal was created after their kind.

When naturalists look at DNA, they admit there is complexity involved. However, the mathematical odds are so astronomical, that in order to come to terms with it, Earth is proposed to be prebiotic to form "hot dilute soup" in which organic compounds could have formed. This isn't science to begin with, but a belief system trying to make evidence fit in itself. How does a creationist interpret this evidence? It's the evidence of a designer.

Naturalists will continually reject the Authority

I could go on with how naturalists come up with proposals to fit the evidence in their worldview. At the heart of what they do, they are making attempts to reject God. For as long as naturalists do not admit their faith, they will hold on to their version of truth and reject God's truth.

The 4 levels of IT Architecture

Written on Thu, 9 March 2017

20 years ago, developing web applications was just a simple straight forward thing. Today, developing web applications is a multi-disciplinary work. I’m going to break down the levels of work while keeping things as simplified as possible.

Think of a web application as a building with 4 levels:

Each level rest on the level before it. You can’t have level 2 without level 1, level 3 without level 2, and level 4 without level 3. The same reasoning that you can’t build a building without the storey before it.

In the simplest of web applications, you can build all 4 levels into a single project. The most complex applications can even have multiple projects in each level.

Level 1: Matrix

The central node to everything else. The brains of everything. The business logic. The data storage platform.

Here are the things you need to consider in this level, but not limited to:

• OS: Linux, Windows, Unix, etc?
• Single server or clustered environment?
• RDBS: MySQL, Oracle, etc?
• NoSQL or not?
• Assets: Filesystem, NAS, S3, etc?
• Backups?
• Data Cache: Memcache, file cache, etc?
• All the required business logic, such as authentication, access control list, machine learning, etc
• Obviously, programming language: PHP, Java, .NET, etc?

Level 2: Connector

A connector is a bridge between the Matrix and the interface. In the simplest of web application, sometimes, this is non-existent. You will only need a connector if your application has a distinct seperation between the Matrix and the interface.

A mail server is an example of a connector. When you develop a web application, you are certainly not going to build your own mail server along with it. You will likely use an external provider, such as Gmail, Hotmail, Yahoo, etc… Your connector will send out emails on behalf of your application.

A connector can also be an API from which other applications to interact with. For example, Facebook API is a connector to Facebook itself. The API allows you to interact with Facebook. So if you are building your own API, you are allowing other applications to interact with your own web application. You will most likely need this if you are building a mobile application.

Here are the things you need to consider in this level, but not limited to:

• What protocol should I use for API, JSON, XML, or binary, for other applications to interact with my application?
• Are there external services that I require to connect with? Such as mail server, Facebook API, etc…
• Do I need authentication to connect to other services? Do I need other applications to authenticate with my application before interacting with it?
• How long will DNS propagation take?

Level 3: Interface

The interface which a user will use to interact with the Matrix through the connecter, such as the web browser, the phone, the tablet, the Xbox, Outlook, Hololens, Oculus, etc…

In your context, I know you explicitly mention about web applications. But web applications can be consumed on mobile phones as well. I also presume that your application has a chance to go beyond a website.

Here are the things you need to consider in this level, but not limited to:

• Web Programming language: Do I use server side scripting language such as PHP, Java? Or do I use client side scripting language, such as Javascript, AngularJS, ReactJS, etc…?
• Device Programming language: If I’m building a mobile application, should I use Java, C#, etc..?
• Mail Client: Text, HTML, or both?
• Background services: Push Notifications for Mobile application? Polling services for updates?
• Device functions: Location Detection? Accelerometer? Camera?

Level 4: Reality

The presentation and the delivery of content, inclusive of text, images, videos, live broadcast, etc…

Here is where the users actually see, touch, and feel your application. It is not restricted to a human user. A robot, such as googlebot, can also be viewing your website on this level. So other than making sure that your website is readable to a human, you would also consider Search Engine Optimisation (SEO).

Here are the things you need to consider in this level, but not limited to:

• Presentation Language: HTML, CSS, Javascript, Flash, etc…
• External loaded files: Javascript libraries, images, videos, documents, etc…
• Sementic Language for robots, such as GoogleBot, OpenGraph crawler, etc…
• Input source: Mouse? Touch Screen? Joystick? Keyboard? Kinect?
• Output Device: Monitor screen? Mega Stadium Multimedia systems? 5.1 Surround sound? Headphones? Augmented reality through Hololens? Mobile screens?
• Web Browser: To which version of browser do I support till for IE, Edge, chrome, FireFox, Safari, and Opera?
• Resolution: Tiny mobile screens to mega displays in concerts?

Typical Simple Use Case

In a typical use case, someone such as yourself, will probably rent a web host from GoDaddy(Maybe). And then from its cPanel, you will instruct it to install wordpress. And that’s it for Level 1.

Now you need to send out emails to your subscribers, so you also get a mail server from GoDaddy(Maybe) and you configure your wordpress to send out emails through GoDaddy SMTP. And that’s it for Level 2.

Now you want to have a nice looking website that can be viewed nicely on mobile phone browsers too. So you look around the internet and downloaded a nice looking template for wordpress. And that’s it for Level 3 and 4.

A (somewhat) Complex Use Case

Level 1
You decided to rent servers from AWS. In Level 1, you decided that the Matrix is going to be in a clustered environment. So you must store Relational Data in a RDS. Your assets must also be stored in S3. You have configure VPN site-to-site configuration, so all data backups go to your office servers. You use Java to build the matrix, but you also use machine learning in your application, which is built on python. As machine learning is computationally intensive, you built a seperate clustered GPU system for your ML needs.

Level 2
Not just a website, you also intend to have mobile applications, PlayStation, Xbox, Hololens. Your web application will have a built in connector to do HTTP calls to the matrix in JSON. You will need to build a seperate connector for your mobile applications, Playstation, Xbox, Hololens. You anticipate that you have high traffic volume, so you add a load balancer to your connectors. Your mail server is Zimbra, which you are hosting on AWS. So you ensure that emails are sent out properly. You also have SMS notifications, so you subscribe to a SMS gateway.

Level 3
As you are building for web browsers, mobiles, PlayStation, Xbox, and Hololens, you build all of these applications in their respective programming language.As you are also using Facebook Login, Google+ Login, and Paypal Login, you have to build these services into every application. You also ensure your emails do not fall into spam folder when it is delivered. On mobile devices, you are accessing camera and location functions. All of these external devices are communicating with Level 2 in either Binary or JSON.

Level 4
You have to take into account of the various mode of input and output, ensuring the best user experience in every device. Due to high volume traffic, you decide to have a Content Distribution Network to lower latency. Robots are also reading your contents, so SEO must be properly done.

Swap Partition on EC2 Ubuntu

Written on Wed, 15 February 2017

If you have a case of having file system as btrfs, you will know that you can't have swap files on such systems. In such case, you probably need a partition. If you're running your server on AWS EC2, then you can even opt for having SSD as your swap partition, especially if your other EBS if on HDD.

Step 1: Create your EBS and attach it to your EC2 instance

You will have to create a new volume in your AWS console or via AWS API.

• Volume Type: GP2 or IO1
  • You can usually settle for GP2, but if you need the extra performance boost, you can go IO1. If you still need better performance, you should just launch an EC2 instance that has more RAM. If you don't mind a performance hit, you can go for st1 or sc1.
• Size: 8GB
  • More capacity if you find yourself needing more. Although keep in mind that if you need more than 2 times the size of your RAM, you might want to consider a better EC2 instance with more RAM instead. I'm going to assume in this tutorial that you are using 8GB RAM.
• Availability Zone: The one which your instance resides in

Once you have created your volume, you must attach it to your instance.

Step 2: Find your newly attached volume

You can find your newly attached volume with:

sudo lsblk

You should see a disk called xvdf, or another letter, that has 8G of space. In this tutorial, I'm assuming your disk is xvdf.

Step 3: Check for existing swap

In this tutorial, I'm assuming you have no swap.

You can check for existing swap with:

sudo swapon --show

If there is no output, that means you have no swap space currently.

You can verify no existing swap with:

free -h

If you see that swap has 0B, that means there is no active swap present in system.

Step 4: Making swap

Format your partition with:

sudo mkswap /dev/xvdf

You should see something like:

Setting up swapspace version 1, size = 8 GiB (8589930496 bytes)
no label, UUID=d3a23c79-5144-47fa-b422-885ebf63e2fc

Take note of your UUID. You will need it.

Step 5: Enabling swap on boot

You need to configure your fstab with the new swap partition.

echo 'UUID=d3a23c79-5144-47fa-b422-885ebf63e2fc none swap sw 0 0' | sudo tee -a /etc/fstab

Be sure to replace your UUID in this command.

Reboot your computer for swap to take effect.

reboot

Step 6: Check your new swap space

Run these commands to see that you have 8G for swap space.

sudo swapon --show
free -h

If you don't see your new swap space, something has gone wrong somewhere as you were following this tutorial.

Step 7: Configuring swappiness (Optional)

Swappiness is a parameter for the system to determine how often your system swaps data out of RAM to swap space. The values are represented from 0 to 100, in percentages. By default, the value is 60.

You must remember that a swap on HDD is time costly, while a swap in SSD is lifespan costly. Since I'm running a server, I would prefer a value closer to 0, only to use RAM when absolutely neccessary. In some use cases, using swap actually increases performance.

Choose your ideal percentage, then run the following:

sudo sysctl vm.swappiness=10

I chose 10 so that it will use swap sparingly.

To make this value permanent during reboots, open /etc/sysctl.conf:

sudo nano /etc/sysctl.conf

Then add the following at the bottom:

vm.swappiness=10

Conclusion

Having swap has many advantages. In some cases, it will safe a technician from certain doom due to application crashes.

For me, I managed to lower my operating cost of running instances in AWS. After all, if I don't mind a bit of performace hit from running swap in SSD. In return, I get to half the cost of the instance running cost.

If you're looking to have a swap file instead of a swap partition, check out my other tutorial.

Swap Space in EC2 Ubuntu

Written on Mon, 13 February 2017

Over the course of running this webserver and zimbra, I realised that there is a need to have swap space whenever you have applications that are memory hungry. My webserver has occasionally run out of memory on t2.nano instance and my zimbra webserver frequently has memory issues, almost always due to MySQL/MariaDB. MySQL/MariaDB certainly is memory hungry for some reasons, so I guess until I can figure out how to optimise these applications, I just have to work with either increasing RAM or having swap space.

The Ubuntu instances will likely not have swap space. You must configure one. In this tutorial, I will make things really easy by making a swapfile in the filesystem instead of creating a partition

Before you proceed with the tutorial, you must take into consideration of several matters. If you EBS volume is Magnetic, sc1, or st1, having a swap will reduce the performance of applications. Spinning disk will always be slower than RAM or SSD. However, if you are gp2 or io1, then you will see noticable performance of having swap on SSD than on HDD. But you will degrade the SSD fast due to many write cycles. Either way, having swap is a very good safeguard and comparatively affordable solution against application error or crashes related to out-of-memory situations.

Incompatibilities

You must also take note if your file system supports swap files. At the time of this writing, btrfs is not compatible with swap. You probably want to create a partition instead.

Step 1: Checking for existing Swap

We can see if the system has any configured swap by typing:

sudo swapon --show

If there is no output, that means you have no swap space currently.

You can verify no existing swap with:

free -h

If you see that swap has 0B, that means there is no active swap present in system.

Step 2: Check available space in file system

We check the available space in the filesystem with:

df -h

Take note of the space space available in /dev/xvda1. If you intend to have swap space on other EBS, then check the available space of it.

Planning your swap space

In a standard Ubuntu installation, you should have 8GB hard disk space, of which, the OS and the applications will consume some. You would probably be left with about 5GB. It is usually recommended to have twice as much swap as your RAM. Of course, you are free to have as much swap as you need. In a t2.nano instances, you will only have 512MB RAM. so I'm going to have 1GB of swap space.

Step 3: Creating Swap File

I'm going to create 1GB of swap space:

sudo fallocate -l 1G /swapfile

We can verify that the correct amount of space was reserved with:

ls -lh /swapfile

You should see something like:

-rw-r--r-- 1 root root 1.0G Feb 13 07:35 /swapfile

Step 4: Enabling swap space

For security reasons, we should only allow users with root privileges to read the contents. All other users should not have access to the swap file.

sudo chmod 600 /swapfile

Verify the permissions change with:

ls -lh /swapfile

You should see something like:

-rw------- 1 root root 1.0G Feb 13 07:35 /swapfile

We now mark the file as swap space with:

sudo mkswap /swapfile

You should see an output like:

Setting up swapspace version 1, size = 1024 MiB (1073737728 bytes)
no label, UUID=0d7257f1-9def-4542-bcba-34b8f50f2822

Now we enable swap:

sudo swapon /swapfile

Verify the swap is enabled with:

sudo swapon --show

You will now see a swap file with 1024M.

You can also check with:

free -h

You will see 1.0G of space for use.

Step 5: Making Swap Permanent

If you reboot your computer, the setting you just did will be gone. You can make swap a permanent feature during reboot.

Add swap file information to fstab with:

echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab

That's it!

Step 6: Configuring swappiness (Optional)

Swappiness is a parameter for the system to determine how often your system swaps data out of RAM to swap space. The values are represented from 0 to 100, in percentages. By default, the value is 60.

You must remember that a swap on HDD is time costly, while a swap in SSD is lifespan costly. Since I'm running a server, I would prefer a value closer to 0, only to use RAM when absolutely neccessary. In some use cases, using swap actually increases performance.

Choose your ideal percentage, then run the following:

sudo sysctl vm.swappiness=10

I chose 10 so that it will use swap sparingly.

To make this value permanent during reboots, open /etc/sysctl.conf:

sudo nano /etc/sysctl.conf

Then add the following at the bottom:

vm.swappiness=10

Conclusion

Swap has many many advantages. In some cases, it will save a technician from certain doom due to application crashes.

Generally swap is the most affordable alternative to getting RAM upgrades, or even CPU upgrades. Use it wisely and you will have a well-oiled affordable machine that will last you very long.

If you have to create a swap partition instead of a swap file, check out my other tutorial on creating a swap partition.