Computer Security Elaine Munn Introduction to Computer Security

Introduction Computer systems and networks are all around us. Online banking Automated supermarket checkouts Online classes Online shopping Online travel resources Computer systems are everywhere. Online banking, ATMs, debit cards E-Bay, Amazon, Half.com for textbooks Expedia, Travelocity, airplane e-tickets

Malware Software with a malicious purpose Virus Trojan horse Spyware Logic Bomb Virus – “a small program that replicates itself and hides itself inside other programs, usually without your knowledge” (Symantec, 2003) Trojan horse - a malicious program disguised as something desirable or harmless Spyware – the fastest-growing category of malware

Malware (cont.) Virus One of the two most common types Usually spreads through e-mail Uses system resources, causing slowdown or stoppage One of the two most common types of malware Usually spreads itself through unsuspecting user’s e-mail Even without malicious payload, rapid replication uses system resources, causing slow down or stoppage

Malware (cont.) Trojan Horse The other most common kind of malware Named after the wooden horse of ancient history The other most common kind of malware Named after the famous wooden horse of ancient history It disguises itself as something benign, something you need or want, i.e. a game, screen saver, account logon, etc It captures your information and returns it to the intruder

Malware (cont.) Spyware The most rapidly growing types of malware Cookies Key logger Spyware is the most rapidly growing type of malware. Cookies: initially a good idea to help users surf the Web, now misused to spy on users Key logger: both in software and hardware, captures all the user’s typing and logs it, capturing passwords, account numbers, credit card numbers, etc.

Malware (cont.) Logic Bomb Lays dormant until some logical condition is met, often a specific date. Spyware is the most rapidly growing type of malware. Cookies: initially a good idea to help users surf the Web, now misused to spy on users Key logger: both in software and hardware, captures all the user’s typing and logs it, capturing passwords, account numbers, credit card numbers, etc.

Compromising System Security Intrusions Attacks that break through system resources Hackers Crackers Social engineering War-driving Intrusions are attacks that break through your system’s resources without authorization Hackers – early internet joy riders, by intent not malevolent Crackers – system intruders, with malevolent intent Social Engineering – intruding into a system using human nature, not technology War driving – driving around looking for unprotected wireless networks

Basic Security Terminology People: Hackers White hats Black hats Gray hats Script kiddies Sneakers Ethical hackers People Hackers – anyone who studies a system through analyzing its flaws White hats – Consider themselves the “good guys” Black hats – Or “crackers” are definitely the “bad guys” Gray hats – Not a common term; refers to individuals who operate out side of the law on occasion Script kiddies – Inexperienced; consider themselves hackers, but only copy the work of others Ethical hackers – Consultants who are hired to do vulnerability assessments on company systems

How do I protect my computer? Antivirus: Whenever Windows is up, it should be running an up-to-date antivirus program. These work in the background, blocking not only viruses, but all sorts of malware.

Firewall: Like an antivirus, this type of program runs in the background at all times. But this one controls the traffic between your PC and the rest of the network (and Internet). Windows comes with a perfectly good firewall, but you should make sure it’s on. Search for firewall and select Windows Firewall in Control Panel. In the left pane, click Turn Windows Firewall on or off.

Updates Make sure Windows updates itself automatically. In Windows 7 or 8, search for and launch Windows Update. Click Change settings in the left pane. If Install updates automatically (recommended) isn’t selected, select it. In Windows 10, search for windows updates and select Windows Updates Settings. Scroll down to the bottom of the window and click Advanced options. Make sure Automatic (recommended) is selected.

Your browser Just like Windows, your browser needs to be up-to-date and secure. Go to your browser’s settings to make sure it updates regularly and that it’s set to block suspicious sites.

Encryption If your PC is stolen, why let the thieves get your secrets, as well. Encrypt your most sensitive files This will encrypt every file in this folder and its subfolders. New files created or dragged here will also get encrypted. Other people will be able to see the files and the file names, but they won’t be able to open the files. Only you—or at least, only someone logged on as you—can open these files.