Windows 8 is built on the rock-solid foundation of Windows 7, and it features many improvements in performance, security, privacy, and system reliability. Refinements to the kernel improve system responsiveness, security, and performance. Improvements in the driver model and tools chain for driver development improve system stability and reliability. And Windows now runs on ARM devices as well as x86 and x64.
It introduces many new security features some of which have been mentioned below:
Metro style apps run in a more secure environment. The have restrictions that control runtime access to sensitive resources. When customers buy the app, they provide consent for the app to use only those capabilities. The app can also ask them to use the resources they previously agreed to, giving customers further control over their data. Apps can read and write to user data stores with an improved data-access model, and the app’s user data is isolated to that app and to that user. All of the user’s connected devices can access this app data.
SmartScreen filter. SmartScreen is a set of sophisticated technologies to help protect you from malicious websites and programs. Whether you’re downloading or running a new program on the desktop, SmartScreen has you covered. SmartScreen continues to provide protection from phishing and socially engineered malware attacks using URL and application reputation and removes unnecessary warnings for programs and publishers with an established reputation. To add another layer of protection, SmartScreen is now integrated with program launch to screen programs downloaded from the web. It also shows new warnings before higher-risk programs can run and will block known malware.
Windows Defender. To ensure legitimate anti-malware protection to all users, Windows 8 provides Windows Defender. It monitors and protects against viruses and other malware in real time and detects and removes malware if your computer becomes infected. With Windows 8, third-party anti-malware software becomes even more effective: by loading approved anti-malware drivers during the boot process, anti-malware software can start from a known good state and continue its vigilant watch over your PC from that point on.
There is some great news for consumers. Windows 8 will now ship with antivirus protection too. Microsoft will be adding features and antivirus definations of Microsoft Security Essentials to the Windows Defender software which is already built in to Windows.
Secured boot. Secured boot stops malware in its tracks and makes Windows 8 significantly more resistant to low-level attacks. Even when a virus has made it onto your PC, Windows will authenticate boot components to prevent any attempt to start malware before the operating system is up and running, using Early-Launch Anti-Malware (ELAM) technology . If the component isn’t correctly signed by Microsoft, Windows will begin remediation and start the Windows Recovery Environment, which will automatically try to fix your operating system.
Windows can further validate the boot process beyond Secured Boot. The startup processes are now signed, protected, and measured. They’re then stored in the TPM chip to prevent rootkit or malware infection. For TPM-based systems, Windows 8 will perform a comprehensive chain of measurements during the boot process, called measured boot, which can be used to validate the boot process to prevent rootkits and other malware.
AppLocker. AppLocker contains new capabilities that enable it to manage both desktop and Metro style applications. IT pros can create security policies that allow or deny specific applications from being run by specific users or groups of users.
BitLocker. Windows 8 delivers a rich set of improvements in BitLocker that help businesses reduce the risk of unauthorized data access. For Windows 8 business customers, BitLocker delivers better performance than today’s software-only encryption by supporting fast, hardware encrypting drives. BitLocker only encrypts sectors that have data, incrementally encrypting the drive as free space is used. The user experience is improved through hard drive pre-encryption with clear key and standard user pin reset.
Windows 8 will also be protected from bootable USB Drives that may be infected with malware.
To learn more you may want download the Windows 8 Developers Guide and the Windows 8 Fact sheet.