Why Is Linux More Secure Than Any Other OS

We Here Many Time People Says Why Linux Is Secure Than Windows And Other OS?

Unfortunately for Windows users, that's just not true--as evidenced by the never-ending parade of patches coming out of Redmond. In fact, one of Linux's many advantages over Windows is that it is more secure--much more. 

For small businesses and other organizations without a dedicated staff of security experts, that benefit can be particularly critical.

But what are the things in Linux that makes it secure than Windows or any other Operating System.
 

Here I will try to throw some light on some of the security features which I know in Linux and believe that these points add up to the construction of a much more secure wall all around the Linux Operating System.

1. Execshield

ExecShield is designed to prevent security breaches caused by software programs written to crawl
through the Internet looking for systems with common vulnerabilities such as worms and viruses. It is enabled in the kernel and works in a way that is non intrusive to the user.

Its goal is not to defend against the expert hacker who has broken into your local network or an employee inside the company who already has access to parts of the network instead its goal is to prevent against intruders using scripts that look for vulnerabilities in the way a program running with root privileges is written.

2. Privileges

Linux systems are by no means infallible, but one of their key advantages lies in the way account privileges are assigned. In Windows, users are generally given administrator access by default, which means they pretty much have access to everything on the system, even its most crucial parts. So, then, do viruses. It's like giving terrorists high-level government positions.

With Linux, on the other hand, users do not usually have such "root" privileges; rather, they're typically given lower-level accounts. What that means is that even if a Linux system is compromised, the virus won't have the root access it would need to do damage systemwide; more likely, just the user's local files and programs would be affected.

That can make the difference between a minor annoyance and a major catastrophe in any business setting.

3. SElinux (Security Enhanced Linux)

SELinux is an implementation of a flexible mandatory access control architecture in the Linux operating system.  The SELinux architecture provides general support for the enforcement of many kinds of  mandatory  access control  policies,including those based on the concepts of Type Enforcement(R), Role- Based Access Control, and Multi-Level Security.

SELinux can potentially control which activities a system allows each user, process and daemon, with very precise specifications. However, it is mostly used to confine daemons like database engines or web servers that have more clearly-defined data access and activity rights. 

This limits potential harm from a confined daemon that becomes compromised. Ordinary user-processes often run in the unconfined domain, not restricted by SELinux but still restricted by the classic Linux access rights.

 4. Social Engineering

Viruses and worms often spread by convincing computer users to do something they shouldn't, like open attachments that carry viruses and worms. This is called social engineering, and it's all too easy on Windows systems. Just send out an e-mail with a malicious attachment and a subject line like, "Check out these adorable puppies!"--or the porn equivalent--and some proportion of users is bound to click without thinking. The result? An open door for the attached malware, with potentially disastrous consequences organizationwide.

Thanks to the fact that most Linux users don't have root access, however, it's much harder to accomplish any real damage on a Linux system by getting them to do something foolish. Before any real damage could occur, a Linux user would have to read the e-mail, save the attachment, give it executable permissions and then run the executable. Not very likely, in other words.

5. IPtables

With the enhanced features available with the IPtables you can implement a greater level of security for your Linux machine.

IPtables  is used to set up, maintain, and inspect the tables of IP packet filter rules in the Linux kernel. Several different tables may be defined.  Each table contains a number of built-in chains and may also contain user-defined chains.

Each chain is a list of rules which can match a set of packets.  Each rule specifies what to do with a packet that matches.   This  is called a 'target', which may be a jump to a user-defined chain in the same table.

6. The Monoculture Effect

However you want to argue the exact numbers, there's no doubt that Microsoft Windows still dominates most of the computing world. In the realm of e-mail, so too do Outlook and Outlook Express. And therein lies a problem: It's essentially a monoculture, which is no better in technology than it is in the natural world. Just as genetic diversity is a good thing in the natural world because it minimizes the deleterious effects of a deadly virus, so a diversity of computing environments helps protect users.

7. PAM (Pluggable Authentication Modules)

Linux-PAM is a system of libraries that handle the authentication tasks of applications (services) on the system.  The principal feature of the PAM approach is that the nature of the authentication is dynamically configurable. In other words, the system administrator is free to choose how individual service-providing applications will authenticate users.

Linux-PAM separates the tasks of authentication into four independent management groups: account management; authentication management; password management; and session management.

account - provide account verification types of service: has the user's password expired?; is this user permitted access to the requested service?

authentication - authenticate a user and set up user credentials. Typically this is via some challenge-response request that the user must satisfy: if you are who you claim to be please enter your password.

password - this group's responsibility is the task of updating authentication mechanisms. Typically, such services are strongly coupled to those of the auth group. Some authentication mechanisms lend themselves well to being updated with such a function. Standard UN*X password-based access is the obvious example: please enter a replacement password.

session - this group of tasks cover things that should be done prior to a service being given and after it is withdrawn. Such tasks include the maintenance of audit trails and the mounting of the user's home directory. The session management group is important as it provides both an opening and closing hook for modules to affect the services available to a user.

8. Audience Size

Hand-in-hand with this monoculture effect comes the not particularly surprising fact that the majority of viruses target Windows, and the desktops in your organization are no exception. Millions of people all using the same software make an attractive target for malicious attacks.

9. Audit

The 2.6 Linux kernel has the ability to log events such as system calls and file access. These logs can then be reviewed by the administrator to determine possible security breaches such as failed login attempts or a user failing to access system files. This functionality, called the Linux Auditing System.
auditd  is  the  userspace component to the Linux Auditing System. It's responsible for writing audit records to the disk. Viewing the logs is done with the ausearch or aureport utilities. Configuring the audit rules is done with the auditctl utility.  

During  startup, the  rules  in  /etc/audit/audit.rules are read by auditctl.

5. How Many Eyeballs

"Linus' Law"--named for Linus Torvalds, the creator of Linux--holds that, "given enough eyeballs, all bugs are shallow." What that means is that the larger the group of developers and testers working on a set of code, the more likely any flaws will be caught and fixed quickly. This, in other words, is essentially the polar opposite of the "security through obscurity" argument.

With Windows, it's a limited set of paid developers who are trying to find problems in the code. They adhere to their own set timetables, and they don't generally tell anyone about the problems until they've already created a solution, leaving the door open to exploits until that happens. Not a very comforting thought for the businesses that depend on that technology.

In the Linux world, on the other hand, countless users can see the code at any time, making it more likely that someone will find a flaw sooner rather than later. Not only that, but users can even fix problems themselves. Microsoft may tout its large team of paid developers, but it's unlikely that team can compare with a global base of Linux user-developers around the globe. Security can only benefit through all those extra "eyeballs."

Once again, none of this is to say that Linux is impervious; no operating system is.

And there are definitely steps Linux users should take to make their systems as secure as possible, such as enabling a firewall, minimizing the use of root privileges, and keeping the system up to date. For extra peace of mind there are also virus scanners available for Linux, including ClamAV. These are particularly good measures for small businesses, which likely have more at stake than individual users do.

It's also worth noting that security firm Secunia recently declared that Apple products have more security vulnerabilities than any others--including Microsoft's