Friday, July 6, 2012

Computer Virus

I am here with a new but very common topic "Computer Virus". So what is this? A computer virus is a programmer or code which can replicate or execute itself and spread one computer to another through media service or network.worms, Trojans, Mal-ware, Ad-ware, phishing and all sorts of viruses we can name.



The History of Computer Virus and most infamous viruses ..........

In 1944:  “Theory of self-reproducing automata”  Von Neumann introduced the  possibility of self-relicating computer code.

In 1960: "Creeper" - One of the first viruses in history.

In 1982: Elk Clone

In 1987: Jerusalem

In 1988: Morris

In 1998: Solar Sunrise Hello Friend ,
In 1999: Melissa

In 2000 May: I Love You

In 2001 July: The Code Red worm

In 2001: Nimda

In 2009: Downadup




HA HA HA ....your machine is infected...........

Data, such as a spreadsheet or word processor document, gets corrupted, altered or unreadable.

Programs that you use regularly won’t start or operate significantly slower.

The amount of free hard disk space or free memory is mysteriously disappearing.

Error messages pop up on your screen.

The time-date stamp or size of a program file change automatically.

Your computer becomes extremely slow even while executing normal tasks.

You find that numerous copies of your files have been created automatically.

Your computer hangs frequently.

Your BIOS gives you a message that something is trying to write to your boot sector, and whether it should allow it.


Largely, there are 10 types of viruses:

Boot sector : Eat the boot sector as like MBR. Example: Parity Boot,Disk Killer.

Browser Hijacker : Spread itself numerous way like when we download hugely. It hijacks browsers function. Example: Nginx .

Direct Action Virus : When we executing the file or directory which is containing this types of virus it comes into action. Example: Vienna virus(1988)

Polymorphic : one of the dangerous virus. It mutates over time or after every execution, changing the code used to deliver its payload. Example: Cascade, Pheonix

Resident Virus : Firstly it takes place into computer memory and then run independently the file which was originally affected. Example: CMJ, MrKlunky  

Multi-partite : Depending on different variables like OS or files it spread in multiple ways. Example: Invader, Flip and Tequila.

Macro Virus: It affects on productivity applications like Microsoft Excel, Words. Example : Melissa.

Fie infector virus : Every common virus which basically effected on files. It use an executable file format, such as .exe, as their host. Example: Sunday.

Web Scripting Virus : malicious sites are sometimes created with purposely infected code, many such cases of virus. Example: XSS virus.

Stealth virus : It can hide itself or disable from memory to avoid antivirus detection. Example:  Frodo, Joshi, Whale.


Finaly it is not all about the bad guy. There are Trojan Horse, Warms, Add-war and others who also come in this big "VIRUS" family.



So How virus work Honey ?


So GIVE ME A SOLUTION BRO........

First of all a "GOOD" antivirus. Here are a few steps that are essential even with anti-virus software installed.

 Create an emergency disk which will contain the DOS version of the antivirus software along with the ability to clean viruses. The emergency disk should be a boot able CD or a boot able floppy. Write-protect the floppy and keep it in a safe store.

Set your anti-virus software to automatically download the updates. If automatic updates are not available, check for updates at least once a week.

Set up the anti-virus software to automatically scan downloads and e-mail.

Set up the anti-virus software to automatically scan any removable media, especially if you copy files from the removable media.

Do not disable the anti-virus software that is residing in the taskbar and monitoring all files.

Schedule a virus scan once every week.

In the settings for the anti-virus software, enable the highest protection possible.

Keep it to scan all files by default (as opposed to only program files).

 Set the setting to automatically clean the file if a virus is found and, if cleaning is not possible, to isolate the file or delete it. This will allow you to schedule automated scanning without your intervention in case a virus is found.

Do not disable logging for any virus scans. Make it a point to view the logs after every scheduled scan or a full-system scan.

DO YOU KNOW ???

If your ISP’s mail server has anti-virus support, all incoming mail will be automatically scanned for malicious code. If any viruses are found, the mail would be deleted/quarantined and a notice would be sent to you.


So we have to use our own buddy ANTIVIRUS.......so how it works ?

1. Signature-based malware detection
2. Behavior-based malware detection
3. Anomaly-based malware detection [Passive detection and Active detection]





Something More............

$ 6.3 billion is the amount that companies lose per day due to virus attacks according to Mcafee’s annual security report. Another report says that around 200 million machines are infected by malware on a daily basis.

Virustotal.com is a amazing website which can scan your file with a pack of antivirus. You can definitely find your choosable Antivirus.