A+ Guide to Managing & Maintaining Your PC, 8th Edition

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Presentation transcript:

A+ Guide to Managing & Maintaining Your PC, 8th Edition Chapter 18 Security Strategies

Objectives Learn how to secure a Windows workstation Learn how to authenticate to a computer or network using a token and about other security techniques to protect a computer or SOHO network and its resources Learn how to recognize, remove, and protect against malicious software A+ Guide to Managing & Maintaining Your PC, 8th Edition

Securing a Windows Workstation Two goals in securing network resources: To protect resources To not interfere with the functions of the system Sometimes these two goals are in conflict with each other A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use Windows to Authenticate Users Controlling access to computer resources is done by: Authentication Proves that an individual is who he says he is Authorization Determines what an individual can do in the system after authentication Assign a password to each account created Best to give user the ability to change the password A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use Windows to Authenticate Users Controlling how a user logs on Normally, a user clicks name and enters password from Welcome screen Malware can sometimes intercept and trick users into providing user accounts and passwords More secure method requires user to press Ctrl+Alt+Del to get to logon A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use Windows to Authenticate Users Updating Windows 7/Vista to use Ctrl+Alt+Del logon Enter netplwiz in search box, press Enter User Accounts box appears Click Advanced tab, check Require users to press Ctrl+Alt+Delete, click Apply and close box A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-3 Change the way users log onto Windows A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use Windows to Authenticate Users Power settings used to lock a workstation Quickest way to lock a workstation is to press the Windows key + L Another method is to press Ctrl+Alt+Delete User clicks Lock this computer To unlock, user must enter password Disable the Guest account Disabled by default and should remain disabled Set up an account for visitors, create a standard account and name it Visitor A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use Windows to Authenticate Users Reset a user password If user forgets password or password becomes compromised the password can be reset For business and professional editions of Windows: Reset password using the Computer Management console For all editions of Windows: use the netplwiz command or Control Panel to reset password A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-10 Reset a user’s password A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use Windows to Authenticate Users Create strong passwords Not easy to guess by humans and computer programs Criteria Use eight or more characters Combine uppercase and lowercase letters, numbers, symbols Use at least one symbol: second through sixth positions Do not use consecutive letters or numbers, adjacent keyboard keys, your logon name, words in any language Do not use same password for more than one system A+ Guide to Managing & Maintaining Your PC, 8th Edition

File and Folder Encryption In Windows, files and folders can be encrypted using Windows Encrypted File System (EFS) Works only with the NTFS file system and business/professional editions of Windows If a folder is marked for encryption, every created in or copied to the folder will be encrypted An encrypted file remains encrypted if moved to an unencrypted folder A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-11 Encrypt a folder and all its contents A+ Guide to Managing & Maintaining Your PC, 8th Edition

Windows Firewall Settings A router can serve as a hardware firewall In addition, a large corporation might use a software firewall (called corporate firewall) installed on a computer between Internet and the network A personal firewall (also called host firewall) is software on a computer to protect that computer Windows Firewall is a personal firewall that protects a computer Automatically configured when you set your network location in the Network and Sharing Center Can also customize the settings A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-12 Three types of firewalls used to protect a network and individual computers on the network A+ Guide to Managing & Maintaining Your PC, 8th Edition

Local Security Policies Using Group Policy Group Policy: controls what users can do with a system and how the system is used Available with business and professional editions of Windows Can set security policies to help secure a workstation Example: require all users to have passwords and to rename default user accounts Follow steps on pages 437-438 to set a few important security policies A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use BitLocker Encryption Encrypts entire Windows volume and any other volume on the drive Works in partnership with file and folder encryption Three ways to use BitLocker Encryption Computer authentication Computer has a chip on motherboard called TPM (Trusted Platform Module) that holds BitLocker key If hard drive is stolen, BitLocker would not allow access without BitLocker key User authentication – startup key stored on USB drive Computer and user authentication – PIN or password required at every startup A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use BitLocker Encryption Provides great security at a price Risk the chance of TPM failure Risk losing all copies of the BitLocker (startup) key Use BitLocker only if the risks of BitLocker giving problems outweigh the risk of stolen data A+ Guide to Managing & Maintaining Your PC, 8th Edition

Use BIOS Features to Protect the System BIOS security features Power-on passwords Supervisor password – required to change BIOS setup User password – required to use the system or view BIOS setup Drive lock password – required to access the hard drive Stored on the hard drive so it will still control access to drive in the event the drive is removed A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-19 Submenu shows how to set a hard drive password that will be written on the drive A+ Guide to Managing & Maintaining Your PC, 8th Edition

Additional Methods to Protect Resources In this part of chapter, you will learn: To securely authenticate users on a large network Physically protect computer resources Destroy data before you toss out a storage device Educate users to not compromise security measure in place A+ Guide to Managing & Maintaining Your PC, 8th Edition

Authenticate Users For Large Networks Smart Cards Small device containing authentication information Keyed into a logon window by a user Read by a smart card reader Transmitted wirelessly Variations of smart cards Key fob Wireless token Memory stripe card Cell phone with token A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-20 A smart card such as this SecurID key fob Figure 18-20 A smart card such as this SecurID key fob is used to authenticate a user gaining access to a secured network A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-21 A smart card with a magnetic strip can be used inside or outside a computer network A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-22 This smart card reader by Athena Smartcard Solutions (www.athena-scs.com) uses a USB connection A+ Guide to Managing & Maintaining Your PC, 8th Edition

Authenticate Users For Large Networks Biometric data Validates the person’s physical body Biometric device - input device that inputs biological data about a person which can identify a person’s: Fingerprints, handprints, face, voice, retinal, iris, and handwritten signatures Retinal scanning scans blood vessels on the back of the eye Considered the most reliable of all biometric data scanning Used for highest level of security by government and military A+ Guide to Managing & Maintaining Your PC, 8th Edition

Physical Security Methods and Devices Suggestions: Keep really private data under lock and key Lock down the computer case Use lock and chain To physically tie computer to a desk or other permanent fixture Privacy filters Fits over the screen to prevent it from being read from a wide angle Use a theft-prevention plate Embed it into the case or engrave your ID information into it A+ Guide to Managing & Maintaining Your PC, 8th Edition

Data Destruction Ways to destroy printed documents and sanitize storage devices: Use a paper shredder Overwrite data on the drive Physically destroy the storage media For magnetic devices, use a degausser Exposes a storage device to a strong magnetic field to completely erase data For solid-state devices, use a Secure Erase utility Use a secure data-destruction service A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-26 Use a degausser to sanitize a magnetic hard drive or tape A+ Guide to Managing & Maintaining Your PC, 8th Edition

Educate Users Important security measures for users Never give out passwords to anyone Do not store passwords on a computer Do not use same password on more than one system Be aware of shoulder surfing Other people peek at your monitor screen Lock down your workstation each time you step away Be on the alert for tailgating When someone who is unauthorized follows the employee through a secured entrance Also when someone continues to use a Windows session A+ Guide to Managing & Maintaining Your PC, 8th Edition

Educate Users Social engineering techniques Don’t forward an email hoax Site to help you debunk a virus or email hoax: www.snopes.com www.viruslist.com www.vmyths.com Phishing: a type of identity theft where the sender of an email scams you into responding with personal data An email message might contain a link that leads to a malicious script A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-27 This phishing technique using an email message with an attached file is an example of social engineering A+ Guide to Managing & Maintaining Your PC, 8th Edition

Educate Users Commonsense rules to protect a laptop: Always know where your laptop is Never check in your laptop as baggage Never leave in overhead bins, keep at feet Never leave a laptop in an unlocked car or hotel room Use a laptop cable lock to secure to table if you must leave it in a hotel room When at work, lock your laptop in a secure place A+ Guide to Managing & Maintaining Your PC, 8th Edition

Dealing With Malicious Software Malicious software (malware, computer infestation) Any unwanted program that means harm Transmitted to a computer without user’s knowledge Grayware Any annoying and unwanted program Might or might not mean harm A+ Guide to Managing & Maintaining Your PC, 8th Edition

What Are We Up Against? Virus program Boot sector virus Adware Replicates by attaching itself to other programs Boot sector virus Virus that hides in the MBR program in the boot sector or in an OS boot loader program Adware Produces unwanted pop-up ads Spyware software Spies on user and collects personal information A+ Guide to Managing & Maintaining Your PC, 8th Edition

What Are We Up Against? Keylogger Worm program Trojan Tracks all keystrokes Worm program Copies itself throughout a network or the Internet without a host program Overloads the network Trojan Does not need a host program to work Substitutes itself for a legitimate program Often downloaded from a web site or a user is tricked into opening an email attachment A+ Guide to Managing & Maintaining Your PC, 8th Edition

What Are We Up Against? Rootkit Virus that loads itself before the OS boot is complete Can hide folders that contain software it has installed Can hijack internal Windows components so it masks information Windows provides to user mode utilities A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 1: Identify Malware Symptoms Pop-up ads plague you when surfing the web Browser hijacking: might be redirected to a web site you didn’t ask for System works much slower than it used to Number and length of disk accesses seem excessive for simple tasks Problems making a network connection Antivirus software displays one or more messages Windows updates fail to install correctly System cannot recognize CD or DVD drive A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 1: Identify Malware Symptoms (cont’d) In Windows Explorer, filenames now have weird characters or file sizes seem excessively large OS begins to boot, but hangs before getting to desktop Receive email messages telling you that you have sent someone spam or an infected message Cannot access AV software sites and cannot update your AV software Message appears that a downloaded document contains macros, or an application asks whether it should run macros in a document A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 2: Quarantine an Infected System Prevent spreading of malware Immediately disconnect from network or turn off the wireless adapter Download antivirus software Disconnect other computers while infected computer connected Connect infected computer directly to the ISP Boot into Safe Mode with Networking Before cleaning up infected system back up data to another media A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 3: Run AV Software Before selecting AV software, read reviews and check out reliable web sites that rate AV software Table 9-1 Antivirus software and web sites A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 3: Run AV Software (cont’d) Run AV software already installed Update software and perform a full scan Run AV software from a networked computer Install and run AV software on the infected computer Purchase AV software on CD or use another computer to download Install and run AV software in Safe Mode Run AV software from a bootable rescue disk or flash drive A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 4: Run Adware or Spyware Removal Software Specifically dedicated to removing adware or spyware Better than antivirus software Windows Defender: antispyware included in Windows 7/Vista Table 9-2 Anti-adware and antispyware software A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 5: Purge Restore Points Some malware hides its program files in restore points stored in System Volume Information folder maintained by System Protection If System Protection is on, AV software can’t clean Turn off System Protection and run AV software Turn System Protection back on after AV software has scanned the system A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 6: Clean Up What’s Left Over Antivirus or antiadware software May not delete files Check Antivirus or antiadware software Web site for instructions to manually clean things up Respond to any startup errors Use MSconfig.exe Program launched from registry Back up and delete registry key Program launched from startup folder Move or delete shortcut or program in the folder A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 6: Clean Up What’s Left Over (cont’d) Research malware types and program files Several Web sites offer virus encyclopedias Check things out carefully Some information is put on web to purposefully deceive Learn which sites you can rely on Delete files Try to delete program file using Windows Explorer Empty the Recycle Bin May have to remove hidden or system file attributes Delete all Internet Explorer temporary files A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 6: Clean Up What’s Left Over (cont’d) Clean the registry Use a registry cleaning utility Use Autoruns at Microsoft TechNet Helps in searching for orphaned registry entries Clean up Internet Explorer Remove unwanted toolbars and home pages Use Programs and Features window or Add or Remove Programs window Disable suspicious add-ons Delete unwanted ActiveX add-ons A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 7: Dig Deeper to Find Malware Processes Use Task Manager to search for malware processes Most processes are registered as running Virus may disguise itself as a legitimate Windows core process Svchost.exe process running under a user name Located somewhere other than C:\Windows\system32 Use Process Explorer at Microsoft TechNet Identifies how processes relate to each other Useful tool for software developers Used to smoke out processes, DLLs, and registry keys eluding Task Manager A+ Guide to Managing & Maintaining Your PC, 8th Edition

processes and gives information about processes Figure 18-35 Process Explorer color codes child-parent relationships among processes and gives information about processes A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 6: Remove Rootkits Rootkit: program using unusually complex methods to hide itself on a system Designed to keep a program working at root level without detection Can prevent display of running rootkit process May display a different name for the process Filename may not be displayed in Windows Explorer Registry editor may not display rootkit registry keys or display wrong information A+ Guide to Managing & Maintaining Your PC, 8th Edition

Figure 18-36 A rootkit can run in user mode or kernel mode A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 8: Remove Rootkits (cont’d.) Rootkit not detected if Windows tools infected Anti-rootkit software Looks for running processes that don’t match up with the underlying program filename Compares files, registry entries, processes provided by the OS to the lists it generates from the raw data Best-known anti-rootkit product is Blacklight by F-Secure (www.f-secure.com) A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 9: Repair Boot Blocks Hard drive boot sectors infected or damaged Repair MBR or OS boot record Launch the Recovery Environment, and access command prompt Use the command bootrec /fixmbr repairs MBR Use the command bootrec /fixboot repairs OS boot record BIOS code corrupted If see an error at POST “Award BootBlock BIOS ROM checksum error” See motherboard manufacturer web site for information A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 10: Enable System Protection and Educate the User If System Protection is still turned off, turn it back on and create a restore point Go over with the user some tips presented earlier in this chapter to keep the system free from malware A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 11: Protect Against Malicious Software Always use a software firewall Windows Firewall is turned on by default Use anti-malware software To avoid conflicts and not slow down performance, it is best to run only one anti-malware program on a computer Keep Windows updates current Keep good backups Keep the User Account Control box enabled A+ Guide to Managing & Maintaining Your PC, 8th Edition

Step-By-Step Attack Plan Step 11: Protect Against Malicious Software (cont’d) Limit the use of administrator accounts Set Internet Explorer for optimum security Use a hard drive image Can reinstall the image if a system gets infected No data is kept on a personal computer Set policy that says all data must be stored on network drives Use network-monitoring software Constantly monitoring the network for unusual activity A+ Guide to Managing & Maintaining Your PC, 8th Edition

Summary The netplwiz command can be used to require user to press Ctrl+Alt+Del to logon to Windows Windows power settings can be used to lock down a workstation after inactivity and require a password to unlock the workstation Encrypted File System (EFS) is used with NTFS volume in Windows business and professional versions Windows Firewall, Group Policy, BitLocker Encryption, and BIOS security features can all be used to help secure a computer and its data A+ Guide to Managing & Maintaining Your PC, 8th Edition

Summary Large networks might use smart cards and biometric data to authenticate a user Physical security can include a locked door, lock and chain, or privacy filter Data can be destroyed using a paper shredder, low-level format, drill, degausser, or Secure Erase utility Educate users against social engineering and how to best protect a laptop when traveling A+ Guide to Managing & Maintaining Your PC, 8th Edition

Summary Malware includes a virus, adware, spyware, keylogger, worm, Trojan, and rootkit Malware symptoms include pop-up ads, slow performance, error messages, file errors, spam, and strange processes running When you suspect a computer is infected, immediately quarantine it To protect a computer against malware, use a software firewall, keep AV software up to date and running, and maintain Windows updates A+ Guide to Managing & Maintaining Your PC, 8th Edition