Dec

Steps to Secure VPS Hosting

Following are the steps to Secure VPS Hosting:

Firewall Installation

Installing firewall and various other related tools such as CSF, sim. These will prevent unauthorized access to your server and from brute force attacks.

CSF (ConfigServer Firewall) http://www.configserver.com/free/csf/install.txt
SIM (System Integrity Monitor) http://www.rfxnetworks.com/sim.php
NSIV (Network Socket Inode Validation) http://www.rfxnetworks.com/nsiv.php
LES (Linux Environment Security) http://www.rfxnetworks.com/les.php
these do not prevent exploits of services which you run on your VPS server. Also need to be aware of the installed firewall and you need to open up the additional ports as needed if you add new services/program.

Securing /tmp partition

Most of the attacks and exploits use /tmp to work out of any propagate themselves. By mounting /tmp with noexec and nosuid (meaning executable cannot be run from /tmp nor with escalated privileges), this stops many of these exploits from being able to do any harm.
You can do it by adding following entry in “/etc/fstab”
====
none /tmp tmpfs nodev,nosuid,noexec 0 0
====
save the file and reboot the VPS, now vps get mounted with “nosuid” and “noexec”

Installing Rkhunter (RootKit Hunter)

Rkhunter is a very useful security scanning tool that is used to scan for trojans, rootkits, backdoors, local exploits and other security problems. It can be useful to detect any failures in your layers of defense. It’s a cron job that scans your server for security problems.

Securing MySQL Database

MySQL is one of the most popular databases on the Internet and it is often used in conjunction with PHP. Besides its undoubted advantages such as easy of use and relatively high performance, MySQL offers simple but very effective security mechanisms. Unfortunately, the default installation of MySQL, and in particular the empty root password and the potential vulnerability to buffer overflow attacks, makes the database an easy target for attacks. You can secure the Mysql using the tutorial.

Securing MySQL Database

Upgrade Apache/PHP, MySQL to latest version

make sure your running the latest secure versions of commons software components. This is the important step in preventing your server getting cracked by common exploits.

Installing Mod_Security

ModSecurity is an open source intrusion detection and prevention engine for web applications and helps in preventing attacks on programs that would be vulnerable; it acts as a powerful shielding application from attacks. ModSecurity supports both branches of the Apache web server.

Disable non-root access to unsafe binaries.

Many exploits use well known executables already on your system as part of their bag of tools. By allowing only privileges to root to these files, you can avoid many attacks to not function.

nabling PHP suEXEC

When PHP runs as an Apache Module it executes as the user/group of the webserver which is usually “nobody” or “apache”. Suexec is a mechanism supplied with Apache that allows to execute CGI scripts as the user they belong to, rather than Apache’s user. This improves security in situations where multiple mutually distrusting users have the possibility to put CGI content on the server.

Disable SSH root access

Allowing the root user to login directly is a major security issue, because a brute force attack can use the known username ‘root’ and concentrate on password variations. By using a unique username (not something like admin) you can reduce the chance of a successful brute force attack. This will force a hacker to have to guess 2 separate passwords to gain root access.

Changing SSH Port

One common security precaution that system admins use is to set ssh to listen on a non-standard port (e.g. port 9989, 9898, etc). It is common for hackers to attempt ssh daemon exploits that tend to be very specific to the version of openssh that is running. By having sshd listen to a different port, instead, then you are reducing the risk of a general port 22 scan and hack. Changing port is an additional layer of security.

Resources: