Preventing Viruses and other Malicious Code.pptx

COMPUTER SCIENCE I- Preventing Viruses and other Malicious Code

1. Preventing Viruses and other Malicious Code

2. What is Computer virus? Lesson 1

3. Computer Virus is a type of computer program that, when executed, replicates itself by modifying other computer programs and inserting its own code. If this replication succeeds, the affected areas are then said to be "infected" with a computer virus, a metaphor derived from biological viruses. Computer viruses generally require a host program. The virus writes its own code into the host program. When the program runs, the written virus program is executed first, causing infection and damage. Computer viruses cause billions of dollars' worth of economic damage each year.

4. Computer Virus A computer virus is a self-spreading piece of software. The viruses disrupt the normal functioning of a computer, damaging its software or stealing its data. The first computer virus was created in 1971 to test whether computer software could self-replicate.

5. Biological virus biological virus is a tiny parasite relying on living cells for survival. Viruses live at the expense of the host, which can be an animal, plant, or bacteria. As soon as it has infected a host cell, a virus starts reproducing, invading other cells, and spreading disease.

6. Biological virus computer virus shows up on your Mac uninvited and starts reproducing itself. If left unchecked, it can cause a lot of damage.

7. What are the Symptoms of a Computer Viruses?

8. 1.Your Computer Slows Down One of the most common computer virus symptoms is slow down. You can know that your computer has been affected by malware if your operating system, computer applications, and internet speed begin to slow down. If you note such a tendency and you’re not running heavy applications or programs, there may be cause for alarm.

9. 2. Crashing If your system crash suddenly appears or the infamous Blue Screen of Death (BSOD) appears more often, then it’s obvious that your computer isn’t operating normally and you should check it.

10. 3. pop-ups One of the most annoying computer virus symptoms are characterized by unwanted pop-ups. If these unexpected pop-ups appear on your system, know that your computer has probably been affected by spyware/virus/malware.

11. 4.Hard Drive Malfunction In case you have discovered that your hard disk is exhibiting unusually high activity even when you aren’t using it, consider checking for malware. However, hard disk malfunction can also be caused by hardware failure.

12. 5.Running Out of Storage Space Computer virus symptoms can be triggered by numerous malicious software through different methods to fill your storage space and may eventually cause it to crash.

13. 6.Unwanted Programs or Messages That Start Automatically Some of the warning signs that you should be suspicious about include: • Windows shutting down suddenly without reason • Programs opening or closing automatically • Strange windows as you boot • Message from windows that you lost access to your drive

14. 7. Disabled Security Solution In case your antivirus doesn’t seem to work or if your update module all of a sudden is disabled, make sure that you check what has happened as soon as possible. There are some types of malware that are built to disable computer security solutions and leave your machine defenseless.access to your drive

15. 8.Sending Strange Messages Automatically The first step is to confirm whether the messages were sent from your account. However, if you discover that you weren’t the sender, then the messages were sent by an uncontrollable application.

16. 9.Unusual Network Activity Sometimes you may not be connected to the internet, and you aren’t running any applications that can connect themselves to the internet, but you still observe high network activity. Such computer virus symptoms can be confirmed by using a good antivirus.

17. 10. Applications If you have tried to start applications from the start menu or desktop of your computer and nothing happens, then your computer may be infected.

18. 11.Error Messages Your computer will know when something is wrong even before you do. One of the noticeable computer virus symptoms includes messages that warn you of missing files.

19. 12.Advertisements Ads are common when browsing. However, when you see them when not browsing, this could be a sign of a virus.

20. 13.Hardware and Accessory Problems In case you have problems with your computer display, for instance color problems or mixing pixels, this can be an indication of malware in your computer. Sometimes network printers also malfunction if they become infected.

21. 14.Sent Emails Viruses can be spread via emails. Therefore, if you note that there are emails in your outbox that you never sent or you receive suspicious emails from a friend, they may be infected.

22. 15.Computer Malfunction Computer viruses can cause your computer to do all kind of strange things. When your computer starts to open files on its own, or acts like keys have been clicked, then you may be experiencing computer virus symptoms.

23. Types of Viruses Lesson 2

24. 1. Malware Short for “malicious software,” malware comes in several forms and can cause serious damage to a computer or corporate network. There are various forms of malware ranging from viruses and worms to Trojans and beyond. Malware is often seen as a catch-all term that refers to any software designed to cause damage to a computer, server, or network. Antivirus software is the most known product to protect your personal devices against malware and is a great start to prevent potential threats. While for enterprises, protecting your endpoint is essential to quickly detect, prevent, and correct advanced threats to your business.

25. 2. Computer Worm The distinctive trait of a worm is that it can self-replicate and doesn’t require human interaction to create copies and spread quickly and in great volume. Most worms are spread though tricking internet users and are designed to exploit known security holes in software. If a machine is infected, the worm can: corrupt files, steal sensitive data, install a backdoor giving cybercriminals access to your computer, or modify system settings to make your machine more vulnerable. A computer worm is malware, just like a virus, but a worm takes a copy of itself and propagates it to other users.

26. 3. Spam Spam refers to unsolicited messages in your email inbox. From the sender’s perspective, spam is a great way to get their message across in an efficient and cost-effective way. While spam is usually considered harmless, some can include links that will install malicious software on your computer if the recipient clicks on it.

27. 4. Phishing Created by cybercriminals attempting to solicit private or sensitive information, phishing schemes tend to be the starting point of nearly all successful cyberattacks. Phishing schemes can disguise itself in many forms, whether its posing as your bank or a common web service, with the sole purpose to lure you in by clicking links and asking you to verify account details, personal information, or passwords.

28. 5. Botnet

29. Botnet malware is a network of computers that have been hijacked or compromised, giving hackers the ability to control infected computers or mobile devices remotely. When the malware is launched on your computer or mobile device, it recruits your infected device into a botnet, and the hacker is now able to control your device and access all your data in the background without your knowledge. A botnet can consist of as few as ten computers or hundreds of thousands, and when bots come together, they are a force to be reckoned with. If a botnet hits your corporate website, it can make millions of requests at once ultimately overloading the servers knocking the website offline, slow web traffic, or affect performance. As many businesses are aware, a website that is offline or has a long lag time can be very costly, resulting in a loss of customers or a damaged reputation.

30. What Causes Computer Viruses?

31. Computer viruses are standard programs; only instead of offering useful resources, these programs can damage your device. For a threat actor to execute a virus on your machine, you must initiate execution. In some cases, an attacker can execute malicious code through your browser or remotely from another network computer. Modern browsers have defenses against local machine code execution, but third-party software installed on the browser could have vulnerabilities that allow viruses to run locally.

32. What Does a Computer Virus Do?

33. The way a computer virus acts depends on how it’s coded. It could be something as simple as a prank that doesn’t cause any damage, or it could be sophisticated, leading to criminal activity and fraud. Many viruses only affect a local device, but others spread across a network environment to find other vulnerable hosts.

34. Examples of Computer Virus

35. 1. Morris Worm Morris Worm or the “Great Worm”, which is believed to be the pioneer among computer worms distributed through the internet. Created to highlight security flaws in Unix systems, its founder Robert Morris, made a fatal error that transformed the worm from a potentially harmless software to a denial-of-service (DDoS) attack machine.

36. 2. Nimda A worm, a virus, and a Trojan horse all in one sounds like something out of a horror movie. But it’s actually a computer virus known as Nimda (admin spelled backwards) that hit the internet back in 2001. Within an hour after its release, Nimda reached the top spot of all reported attacks. No wonder, since the worm used five different transmission routes.

37. 3. ILOVEYOU The virus used emails as a transmission channel, disguising itself as a love letter from one of its victim’s contacts. The malware was hidden in the attachment called “LOVE-LETTER-FOR-YOU.TXT.vbs”. Clicking on it activated a Visual Basic script (a programming language which allows programmers to modify code), and the worm started overwriting random files on the user’s PC. The worm also sent copies of itself to all contacts in the user’s address book.

38. 4. SQL Slammer Outages in 911 service in Seattle,the crash of the Bank of America’s ATM service, and cancellation of several Continental Airlines flights - these are just a few examples of what SQL Slammer (or simply Slammer) is capable of. It sparked at 05:30 UTC on January 25, 2003, infecting its first server. Once the job was done, Slammer spread rapidly, doubling the number of victims every few seconds, and just ten minutes after it was released in the wild, the number of infected computers grew to 75,000. Slammer dramatically slowed down worldwide internet traffic, brought down several important systems, caused a huge panic and more than one billion dollars of damage.

39. 5. Stuxnet The destructive power of computer viruses can make them weapons of mass digital destruction, and Stuxnet became the first one. Unlike any other virus or malware of that time, Stuxnet was developed by the US and Israeli government engineers to disrupt Iran’s nuclear program. Spread via a USB thumb drive, it targeted Siemens industrial control systems, causing centrifuges to mysteriously fail and self-destroy at a record rate.

40. 6. CryptoLocker CryptoLocker is not like a typical computer virus that causes harm and spreads itself. It’s ransomware: a kind of malware that takes your files hostage, holding them for ransom. CryptoLocker used a trojan disguised as a PDF file that was spread through email attachments. Surprisingly enough, CryptoLocker caused no harm to the computer itself and didn’t show up until the encryption was done. If you haven’t backed up your files, the only way to restore them was by paying a ransom.

41. 7. Conficker If there is a flaw in the system, somewhere down the line, it will undoubtedly be exploited. Conficker , Downup , Downadup , Kido - these are all computer virus names that appeared on the internet in 2008. It used the MS08-067 Windows system vulnerability and advanced malware techniques to propagate and install itself into the system. These techniques included copying itself to shared folders and exploiting the AutoRun utility for removable media.

42. 8. Tinba Tinba is the pet name for the Tiny Banker Trojan that hit the headlines in 2016. As the name suggests, its main target was financial institution websites. Tinba used man-in-the-browser attacks and network sniffing to get users’ banking information.

43. 9. Shlayer Shlayer disguised itself as updates for Adobe Flash Player (that’s where its name comes from). When launched, it ran a series of shell scripts to proliferate various adware or potentially unwanted applications. In most cases, users got the Shlayer virus when visiting untrustworthy Torrent websites, clicking on the advertisements, or downloading shady files.

44. How to Prevent Computer Viruses?

45. 1. Install antivirus software Antivirus should run on any device connected to the network. It’s your first defense against viruses. Antivirus software stops malware executables from running on your local device.

46. 2.Don’t open executable email attachments Many malware attacks including ransomware start with a malicious email attachment. Executable attachments should never be opened, and users should avoid running macros programmed into files such as Microsoft Word or Excel.

47. 3. Keep your operating system updated Developers for all major operating systems release patches to remediate common bugs and security vulnerabilities. Always keep your operating system updated and stop using end-of-life versions (e.g., Windows 7 or Windows XP).

48. 4. Avoid questionable websites Older browsers are vulnerable to exploits used when just browsing a website. You should always keep your browser updated with the latest patches, but avoiding these sites will stop drive-by downloads or redirecting you to sites that host malware.

49. 5.Don’t use pirated software Free pirated software might be tempting, but it’s often packaged with malware. Download vendor software only from the official source and avoid using software that’s pirated and shared.

50. 5.Don’t use pirated software Free pirated software might be tempting, but it’s often packaged with malware. Download vendor software only from the official source and avoid using software that’s pirated and shared.

51. Anti-Virus Software

52. Anti-Virus Software that is created specifically to help detect, prevent and remove malware (malicious software). Antivirus is a kind of software used to prevent, scan, detect and delete viruses from a computer. Once installed, most antivirus software runs automatically in the background to provide real-time protection against virus attacks.

53. 1. Avast! Free Antivirus Avast Antivirus is a family of cross-platform internet security applications developed by Avast for Microsoft Windows, macOS, Android and iOS. ... It is a cross-platform solution that includes antivirus protection, web threat scanning, browser protection, and a cloud management console.

54. 2. Panda Cloud Antivirus Panda Dome is 100% safe to use. It is a legitimate antivirus that comes from a highly reputable cybersecurity company. It uses advanced scanning technology to block the latest malware and cyberattacks. It's designed to protect against the latest malware threats, including viruses, spyware, and ransomware.

55. 3. Microsoft Security Essentials Microsoft Security Essentials is an antivirus software product that provides protection against different types of malicious software, such as computer viruses, spyware, rootkits, and trojan horses.

56. 4. Avira AntiVir Personal Edition All versions of Avira Antivirus offer Real-time protection against malware. This feature monitors and scans all the files you access, copy, or otherwise interact with, letting you know if they are safe or infected. In case of danger, Avira Antivirus won't let the suspicious file make changes to your device

57. 5. AVG Anti-Virus Free Edition AVG AntiVirus for Android guards your mobile phone against malware attacks and threats to your privacy. We give you on-the-go protection against unsafe apps, anti-theft locker & tracker, and plenty more security and performance features.

58. 6. Comodo Antivirus Comodo Antivirus is a fairly good antivirus program. Prevents viruses and malware from causing harm to your computer before it's too late. Cloud-based antivirus scanning helps users scan and identify malicious files even if they are not equipped with up-to-date virus definitions.

59. 7. Immunet Protect FREE a malware and antivirus protection system that utilizes cloud computing to provide enhanced community-based security. It works in the cloud, keeping your computer working free. It offers good protection against bots, worms, viruses, trojans, keyloggers, and spyware, so a full protection

60. 8. PC Tools AntiVirus Free PC Tools AntiVirus is one of the most basic antivirus programs you will find. PC Tools iAntiVirus is free antivirus software for Intel based Apple Macintosh computers running Mac OS 10.5 (Leopard) and Mac OS 10.6 (Snow Leopard) initially released in June 2008, used to detect and remove malware, spyware and malicious exploits, using both signature-based and heuristic detection.

61. 9. Malwarebytes Malwarebytes offers one of the best antivirus programs to protect computers against malware, hacks, viruses, ransomware, and other ever-evolving threats to help support a safe online antivirus experience. ... It removes all traces of malware, blocks the latest threats, and is a fast virus scanner.

62. 10. ClamWin Free Antivirus An open-source program ClamWin , is reasonably good protection for your computer. The users receive several useful features free of charge. Specifically, using ClamWin antivirus, you have an opportunity to scan your device, protect it against viruses and malware.