For everyone’s information, it is not true that Linux is somehow resistant to malicious attacks. A vast collection of Linux systems may, in fact, be forfeited. Nevertheless, the Trojan is available in a download that should have no bearing on Linux in a business setting.

A thread from Unreal IRCd Forums exclaims that this is very embarrassing to discover that the Unreal 3.2.8.1.tar.gz file on their mirrors has been replaced with a version with a backdoor (trojan) in it. It is said there that the backdoor allows a person to perform any command with the privileges of the user running the ircd. The backdoor runs regardless of any user restrictions, even when you have a passworded server or hub that doesn’t allow any users in.

This post was dated November 2009 and it seems that nobody has noticed it until now.
Technically speaking, Unreal IRC refers to the Internet relay chat platform. It can be safe to assume that there is a pretty good number of Linux systems out there compromised by a backdoor Trojan. None of those systems should be present in business because of possible company identity theft.

At the end of the UnrealIRCd Forums post, they said that they did not check the files on all mirrors regularly and did not sign releases through PGP/GPG. This is a lesson for everybody, because files should be checked regularly and sign releases through PGP/GPG always.

With the poor security provided by Linux, anyone can be confident and set aside the checking and assuring that the software is not compromised. Linux makes up approximately less than two percent of the overall OS market, making it to be an unattractive target for attackers. This means that Linux owners are almost defenseless from attacks. Nonetheless, Linux experts know that the operating system is not bulletproof.
Linux and its accompanying tools and applications have hundreds of vulnerabilities. Linux OS however is hard to exploit vulnerability. Its open source vulnerabilities are fixed in hours rather than months.

To conclude, Linux is not resistant to attack. Linux systems in a business environment should not be running Unreal, though Unreal is not the only compromised software available.

Though Linux does not have major threats compared to Windows systems, it can’t be ignored that there are still threats to avoid. Even if such threats would not be exploited through a quickly-spreading worm, they can still lead to problems to systems. If you are using Linux, always check and make sure that your system is not compromised by a backdoor Trojan.