Computer viruses by email

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. Also known as Downup or Downadup , Conficker is a worm of unknown authorship for Windows that made its first appearance in The name comes form the English word, configure and a German pejorative.

It infects computers using flaws in the OS to create a botnet. The malware was able to infect more than 9 millions computers all around the world, affecting governments, businesses and individuals. The worm works by exploiting a network service vulnerability that was present and unpatched in Windows. Once infected, the worm will then reset account lockout policies, block access to Windows update and antivirus sites, turn off certain services and lock out user accounts among many.

Then, it proceeds to install software that will turn the computer into a botnet slave and scareware to scam money off the user. Microsoft later provided a fix and patch with many antivirus vendors providing updates to their definitions.

Believed to have been created by the Israeli Defence Force together with the American Government, Stuxnet is an example of a virus created for the purpose of cyberwarfare , as it was intended to disrupt the nuclear efforts of the Iranians. The computer worm was designed to attack industrial Programmable Logic Controllers PLC , which allows for automation of processes in machinery.

When you are prompted, use the arrow keys to highlight Safe Mode with Networking , and then press Enter. Click the Start button and check whether the rogue security software appears on the Start menu. If it's not listed there, click All Programs and scroll to find the rogue security software's name.

Right-click the name of the rogue security software program, and then click Properties. In the Properties dialog box, check the path of the rogue security software program that is listed in Target. Note The folder name frequently is a random number. In the Program Files window, click Program Files in the address bar.

Scroll until you find the rogue security software program folder. For example, XP Security Agent Go to the Microsoft Safety Scanner website. If you suspect that your computer is infected with rogue security software that was not detected by using Microsoft security solutions, you can submit samples by using the Microsoft Malware Protection Center submission form.

Microsoft Defender Offline is an anti-malware tool that helps remove difficult to eliminate viruses that start before Windows starts. Starting with Windows 10, Microsoft Defender Offline is built-in. Click Download the 32 bit version or Download the 64 bit version , depending on which operating system that you are running. If you're unsure of which operating system that you are running, see Is my PC running the bit or bit version of Windows.

When you are prompted, press a key to select an option to use to start your computer, such as F12, F5, or F8, depending on the kind of computer that you are using.

Use the arrow key to scroll to the drive where you installed Microsoft Defender Offline file. Microsoft Defender Offline starts and immediately scans for malware. Confirm that the Windows firewall is turned on. See Turn Microsoft Defender Firewall on or off for instructions on how to do that on modern versions of Windows. In the Search box, type firewall, and then click Windows Firewall.

In the left pane, click Turn Windows Firewall on or off you may be prompted to enter your administrator password. Only download programs from sites that you trust. If you're not sure whether to trust a program that you want to download, enter the name of the program into your favorite search engine to see whether anyone else has reported that it contains spyware. Read all security warnings, license agreements, and privacy statements that are associated with any software that you download.

Never click "Agree" or "OK" to close a window that you suspect might be spyware. Be wary of popular "free" music and movie file-sharing programs, and make sure that you understand all the software packaged with those programs. Use a standard user account instead of an administrator account. An administrator account can access anything on the system, and any malware run with an administrator account can use the administrator permissions to potentially infect or damage any files on the system.

Beware of virus hoaxes Do not take action regarding virus warnings that are received via email until you verify if the warning is genuine; instructions in the email hoax may ask you to perform tasks on your computer that may harm it and your data.

Check with an authoritative source to determine if the email is a hoax. Beware of links to malicious websites Do not click on a hyperlink contained in an email or instant message if you do not know where the hyperlink will take you — even if you know the email sender. Determine what the link is before clicking on it. LifeLock identity theft protection is not available in all countries. All rights reserved. Firefox is a trademark of Mozilla Foundation. App Store is a service mark of Apple Inc.

Alexa and all related logos are trademarks of Amazon. Microsoft and the Window logo are trademarks of Microsoft Corporation in the U. The Android robot is reproduced or modified from work created and shared by Google and used according to terms described in the Creative Commons 3. Other names may be trademarks of their respective owners. Internet Security Centre. Norton UK Blog. CryptoLocker When it comes to malware, ransomware is the new kid on the block.

But why was it so brutal? Source: Shutterstock Well, in malware was a bit of a myth. MyDoom MyDoom is considered to be the most damaging virus ever released—and with a name like MyDoom would you expect anything less? Tip: never open a link in an email unless you know exactly what it is. Cost of the malware: An exact cost is yet to be calculated. Slammer While most of the malware on this list strictly hit computers, Slammer was created with broader ambitions. Source: Stocksnap 8.

Stuxnet Stuxnet is easily the scariest virus on the list as it was built by government engineers in the US with the intention of obstructing nukes from being built in Iran.