Seeksadmin Blog

With the growth of the internet also came the growth of hacking. It has increased so much so that according to Zone-H there are over 2,500 recordered hacks each day. Some people may be suprised by this figure, others wont be. In my opinion that is not the suprising fact, the shocking fact is that the number of reported hacks is growing by 40% each year!!! Are the hackers getting smarter?

Generally the hackers will get in due to one of three reasons:

1. Out of date scripts - Everything from Kernels to Apache have updates and a lot of these updates are to fix security bugs. So if you are running out of date scripts with known security holes. A lot of hackers will take advantage of these holes and gain root access to your server
2. Insecure Scripts - Most of the hack attempts that we have to deal with at Seeksadmin are due to insecure scripts such as PHPbb, Vbulliten or many other common scripts. If these are not kept up to date they are very dangerous allowing a hacker to gain root access.
3. Insecure Passwords: Not much explanation is needed, if you have a short or weak password it is easier to guess and it can easily be brute forced.

So what can you do? Well keep everything up to date, and use a decent password? It wont ensure that you are 100% secure however it will go a long way to stopping you being hacked.

At the moment Seeksadmin is concentrating on security and we are trying to raise awareness in security and how to keep your system secure. In accordance with this we are offering a FREE remote scan and a $5 local scan. After these scans you will recieve the security holes in your system and we will reccomend a few things you can do to help secure your system. We also have free security consultation so if you have any questions please contact us at sales[@]seeksadmin[dot]com

There are a few ways to sort server security, but one of the major ways to harden your server is to secure SSH. On a default machine you login as root directly, on the default port. This means you are susceptable to brute force and all other sorts of attacks. What I am going to write about is a short and simple guide about how to secure your SSH and what this does. You dont have to do all of these allthough I would deeply reccomend doing the steps below.
1. Changing SSH Protocol

I guess a good place to start would be what are the differences between the two SSH protocols (1 and 2), as not many people know this. You dont need to know, but I think that you should know the reasons you are doing this. I will try to cut the crap out of it and keep it simple. Basically SSH2 uses seperate protocols for transport, authentication and connections, splitting all your data up making it just that little bit more secure. It also has stronger cryptographic integrity checks and has better encryption. Basically what I am trying to say (but in tech talk) is that this is one change you should always make. Now lets get on to making the change.

Step 1) Use nano, pico or vi (your favourite text editor) to open up /etc/ssh/sshd_config for editing

Step 2) Find the Line #Protocol 2,1

Step 3) Uncomment the line and change it to

Protocol 2

2. Changing the SSH port

This is what we like to call security by obscurity, it is one extra thing the hacker has to guess before he can get in, although practically a port scan would be able to find the port. However i have found that changing the port does stop a lot of brute force attacks from occouring.

NOTE: Make sure you add the port you want to use to the firewall AND/or add yourself to the allow list so you can connect to the port and dont lock yourself out.

Step 1) Again open up /etc/ssh/sshd_config with your favourite editor

Step 2) Find the line #Port 22

Step 3) Uncomment the line and replace with the following (where port 2777 is a random, unused port)

Port 2777

NB: To find out if the port is being used use the comand lsof -i:portnumber eg lsof -i:2777

3. Disable Direct Root Login

Unlike the other steps we have used this requires a bit more than editing the config file, but its not hard so dont worry about it. Again this is a little of security by obscurity adding an extra layer the hacker/cracker has to get through if he wants access to your machine, making that bit harder.

A lot of other guides you will see will tell you to add a cPanel account etc etc, but lets just make it easier shall we.

Step 1) Type the following in SSH replacing username with a random username eg sekadmin

adduser sekadmin

Step 2) Now lets give sekadmin a password

passwd sekadmin

You will now be given a password prompt twice. Make sure the word is not a dictoinary word, I would reccomend looking at my password article for the best password.

Step 3) Now we need to give sekadmin, the correct privilages so he can su - to root.

Step 4) Open up /etc/group with your favourite text editor. Find the line that starts with “wheel” and add your username on at the end of the line. Then close and save the file.

Step 5) Now you will need to test the login works so create a NEW ssh session and try to connect using the username that you just created. Once logged in type “su -” and then the root password to see if that works. If it works everything went ok and you continue on to the next step

Step 6) Once again open up our favourite file /etc/ssh/sshd_config in your text editor

Step 7) Find the line #PermitRootLogin yes, uncomment it and change it to no.

Other Methods

There are also some other methods that you can use. One of the other methods I like to use is binding SSH to an IP. If you do this, the best thing to do is use a spare IP that is not being used by a website. This will offer the most security.

Anouther great thing to do is to disable password logins totally and use an ssh key. I will not write anything about that here, because it can be a blog post on its own for a rainy day

AFTER all changes

Just before I forget, to make all your changes take effect you will have to restart ssh

service sshd restart

A common problem for many people is remembering their passwords and at the same time making it cryptic enough. I thought I would share my password “remembering” techniques with you, which will help you keep things secure. There are three main methods you can use and I will describe that below.

Rythm/Pattern

Now it may sound weird to have rythm in your password, but when you think about it, it isn’1 too strange. It is all about memory, and you are more likely to remember a password when it has some rythm to it, that you can remember. For example remembering a password such as

sardines0012a

is not going to be easy. (At least I dont think so). Whereas if you have a password with rythm/a pattern

sand00handx

its much easier to remember.

Words

Anouther method that can also be very easy to use is to remember a word and then add your birth date on the end. An example of this is

Seeksadmin1980

This is very effective and very easy to remember as its 2 very memorable facts. It is also pretty hard to guess unless you know what word I had use and what number (it doesnt have to be birthdate, it could be the date you ordered the server)

Pattern

Now this is my favourite and preffered method. This is also different to the pattern/rythm method i described above. So what is it about? Well thats pretty simple, you make a patern on your key board. Here is an example

!ӣ$%67890

if you are very clever you will have noticed that is holding the shift key pressing 1 to 5 and then letting go of shit and pressing the rest of the numbers. It is very easy to remember as its just a pattern on the keyboard. It does not really require you to remember each number/letter just the pattern. The last example ill give is

zaqwsx.;[]‘/

Which is z -> q, w->x ,->[, ]->/. This type of password is pretty much impossible to guess, and yet in my opinion is one of the easiest to remember.

Other Tips

Vary the methods you use of remembering your passwords and of course vary the passwords you use. Whether its something simple such as changing 1 digit for each server or adding the server name on the end of the password, it is important that the servers have different passwords. If you have a secure password, this is one less way a hacker can gain access to your system.

I am sure many of you will be thinking that it is our job to secure your servers and you are right, but much of this you need to know and it will do no harm in you knowing. So if you dont feel like you can do anything here, just open a ticket and we will do it for you. Everything here is pretty simple, and this will be good for anyone who wants to learn, and be slightly more independent.

This guide is mainly for WHM and cPanel as the things are made much easier with cPanel and WHM however we can do them even if you dont have it.

1. Shell Limits

You should enable shell resource limits to prevent users from consuming all the server resources. DDOS exploits typically do this. A quick way to set this for people using WHM is in the root WHM reseller go to Shell Fork Bomb Protection

2. Background Process Killer (People using WHM)

In WHM enable each item in WHM -> Background Process Killer, to remove any IRCs or other malicious bots

3. Apache

In Apache RLimitCPU and RLimitMEM should be set to stop any spammers or DDOSers using all the processes on your server. You can do this in WHM in the Modify Apache Memory Usage page.

You should also make sure that mod_userdir is disabled apart from one main domain, or just make sure its disabled totally, otherwise hacks may use it to try and hide their activities.

You should also enable SUEXEC to reduce the risk of hackers accessing all your sites if the server is comprimissed.

4. PHP

In the php ini (you can find the location via a php info file) you should change enable_dl to Off. This prevents users from loading php modules that effect everyone on the server. Note: IF you use dynamic libs like ioncube you will have to load them directly from the php.ini

You should also change the disable functions to
disable_functions = show_source, system, shell_exec, passthru, exec, phpinfo, popen, proc_open
Some webscripts break with these so you may have to remove a few, but these scripts are dangerous

You need to make sure PHP open_basedir is enabled. In WHM you can do this via WHM -> Tweak Security -> php open_basedir tweak. This prevents PHP scripts from straying outside of their account.

PHPSuExec can reduce the risks of hackers accessing all the sites on the server via a compromised PHP web script. There are some side effects of this, but this is a much safer method. If your server is full I would not recommend it, but on
brand new servers this is the best thing to do as its safer.

5. Control Panel

Make sure your control panel is updated to the latest stable version regularly.

Make sure that SSL login is forced, ie the secure ports. In WHM you can do this via WHM -> Tweak Settings -> Always Redirect users to the ssl/tls ports when visiting /cpanel, /webmil etc

Make sure boxtrapper is DISABLED. The reason for this is that if its enabled you can easily be listed in an RBL and usually has the effect of increasing overall spam load not reducing it.

Make sure you have some sort of limit of emails sent per hour

Make sure users CAN NOT reset passwords via email