World record computer virus

Macro viruses are written in the same macro language used for software applications. Such viruses spread when you open an infected document, often through email attachments.

You can take two approaches to removing a computer virus. One is the manual do-it-yourself approach. The other is by enlisting the help of a reputable antivirus program.

Want to do it yourself? There can be a lot of variables when it comes to removing a computer virus. This process usually begins by doing a web search. You may be asked to perform a long list of steps. If you prefer a simpler approach, you can usually remove a computer virus by using an antivirus software program. For instance, Norton AntiVirus Basic can remove many infections that are on your computer. The product can also help protect you from future threats.

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Not for commercial use. Please login to the portal to review if you can add additional information for monitoring purposes. Security Center Malware What is a computer virus? July 23, Join today. Cancel anytime. Start Free Trial. How does a computer virus attack? How do computer viruses spread? What are the signs of a computer virus?

A computer virus attack can produce a variety of symptoms. Here are some of them: Frequent pop-up windows. Pop-ups might encourage you to visit unusual sites. Besides that, infections also spread while connecting with already infected removable storage devices, such as USB drives. It is quite easy and simple for the viruses to sneak into a computer by dodging the defense systems.

A computer virus operates in two ways. The first kind, as soon as it lands on a new computer, begins to replicate. The second type plays dead until the trigger kick starts the malicious code. In other words, the infected program needs to run to be executed.

Therefore, it is highly significant to stay shielded by installing a robust antivirus program. The primary purpose can involve stealing passwords or data, logging keystrokes, corrupting files, and even taking control of the machine. Subsequently, the polymorphic malware development in recent times enables the viruses to change its code as it spreads dynamically.

This has made the virus detection and identification very challenging. Robert Thomas, an engineer at BBN Technologies developed the first known computer virus in the year The message displayed on infected Apple Computers was a humorous one.

The virus was developed by Richard Skrenta, a teenager in the year A computer virus is one type of malware that inserts its virus code to multiply itself by altering the programs and applications.

The computer gets infected through the replication of malicious code. Computer viruses come in different forms to infect the system in different ways. Find some of the most common type of computer viruses here,. Boot Sector Virus — This type of virus infects the master boot record and it is challenging and a complex task to remove this virus and often requires the system to be formatted.

Mostly it spreads through removable media. Direct Action Virus — This is also called non-resident virus, it gets installed or stays hidden in the computer memory. It stays attached to the specific type of files that it infect.

Resident Virus — Unlike direct action viruses, resident viruses get installed on the computer. It is difficult to identify the virus and it is even difficult to remove a resident virus. Multipartite Virus — This type of virus spreads through multiple ways. It infects both the boot sector and executable files at the same time. Polymorphic Virus — These type of viruses are difficult to identify with a traditional anti-virus program.

This is because the polymorphic viruses alters its signature pattern whenever it replicates. Overwrite Virus — This type of virus deletes all the files that it infects. The only possible mechanism to remove is to delete the infected files and the end-user has to lose all the contents in it.

Identifying the overwrite virus is difficult as it spreads through emails. This is called so as they fill up the empty spaces between the code and hence does not cause any damage to the file. File infectors: Few file infector viruses come attached with program files, such as. Some file infector viruses infect any program for which execution is requested, including.

Consequently, when the particular program is loaded, the virus is also loaded. Besides these, the other file infector viruses come as a completely included program or script sent in email attachments. Macro viruses: As the name suggests, the macro viruses particularly target macro language commands in applications like Microsoft Word. The same is implied on other programs too. In MS Word, the macros are keystrokes that are embedded in the documents or saved sequences for commands.

The macro viruses are designed to add their malicious code to the genuine macro sequences in a Word file. However, as the years went by, Microsoft Word witnessed disabling of macros by default in more recent versions. Thus, the cybercriminals started to use social engineering schemes to target users. In the process, they trick the user and enable macros to launch the virus. Since macro viruses are making a come back in the recent years, Microsoft quickly retaliated by adding a new feature in Office The feature enables security managers to selectively enable macro use.

As a matter of fact, it can be enabled for trusted workflows and blocked if required across the organization. As the name says it all, the virus after attacking the computer starts overwriting files with its own code. Not to be taken lightly, these viruses are more capable of targeting specific files or applications or systematically overwrite all files on an infected device. On the flipside, the overwrite virus is capable of installing a new code in the files or applications which programs them to spread the virus to additional files, applications, and systems.

Polymorphic Viruses: More and more cybercriminals are depending on the polymorphic virus. It is a malware type which has the ability to change or mutate its underlying code without changing its basic functions or features. This helps the virus on a computer or network to evade detection from many antimalware and threat detection products. Since virus removal programs depend on identifying signatures of malware, these viruses are carefully designed to escape detection and identification.

When a security software detects a polymorphic virus, the virus modifies itself thereby, it is no longer detectable using the previous signature. Resident Viruses: The Resident virus implants itself in the memory of a computer. Basically, the original virus program is not required to infect new files or applications. Even when the original virus is deleted, the version stored in memory can be activated. This happens when the computer OS loads certain applications or functions.

Rootkit Viruses: The rootkit virus is a malware type which secretly installs an illegal rootkit on an infected system. This opens the door for attackers and gives them full control of the system. The attacker will be able to fundamentally modify or disable functions and programs.

Like other sophisticated viruses, the rootkit virus is also created to bypass antivirus software. The latest versions of major antivirus and antimalware programs include rootkit scanning. The Boot-record Infectors infect executable code found in specific system areas on a disk.

Boot viruses are no more common these days as the latest devices rely less on physical storage media. Use a professional, email service such as Runbox. Subscription services provide higher levels of security and support. Make sure that your Runbox virus filter is activated. Use the Webmail interface at www. Screen your email first, and delete suspicious-looking and unwanted messages before downloading the legitimate email to your local email client. Make sure your computer has updated anti-virus software running locally.

It will then launch a denial of service attack on several IP address, famous among them was the attack on the White House website. It also allows backdoor access to the server, allowing for remote access to the machine.

The most memorable symptom is the message it leaves behind on affected web pages, "Hacked By Chinese! A total of million servers were affected, which is amazing when you consider there were 6 million IIS servers at the time. Named after an exotic dancer from Florida, it was created by David L. Smith in It started as an infected Word document that was posted up on the alt. This got people curious and when it was downloaded and opened, it would trigger the macro inside and unleash its payload.

It also sometimes corrupted documents by inserting a Simpsons reference into them. Smith was eventually caught when they traced the Word document to him. The file was uploaded using a stolen AOL account and with their help, law enforcement was able to arrest him less than a week since the outbreak began.

He cooperated with the FBI in capturing other virus creators, famous among them the creator of the Anna Kournikova virus. A Windows worm first discovered in , it was created by computer science student Sven Jaschan, who also created the Netsky worm.

While the payload itself may be seen as simply annoying it slows down and crashes the computer, while making it hard to reset without cutting the power , t he effects were incredibly disruptive, with millions of computers being infected, and important, critical infrastructure affected. The worm took advantage of a buffer overflow vulnerability in Local Security Authority Subsystem Service LSASS , which controls the security policy of local accounts causing crashes to the computer.

It will also use the system resources to propagate itself to other machines through the Internet and infect others automatically. This led to more than a million infections , taking out critical infrastructures, such as airlines, news agencies, public transportation, hospitals, public transport, etc. Jaschen was tried as a minor and received a 21 month suspended sentence. Zeus is a Trojan horse made to infect Windows computers so that it will perform various criminal tasks.

The most common of these tasks are usually man-in-the-browser keylogging and form grabbing. The majority of computers were infected either through drive-by downloads or phishing scams. First identified in , it managed to compromise thousands of FTP accounts and computers from large multinational corporations and banks such as Amazon, Oracle, Bank of America, Cisco, etc. Controllers of the Zeus botnet used it to steal the login credentials of social network, email and banking accounts.

The entire operation was sophisticated, involving people from around the world to act as money mules to smuggle and transfer cash to the ringleaders in Eastern Europe. In late , the creator of Zeus announced his retirement but many experts believe this to be false.