A new study from BeyondTrust, a software developer focused on solutions for managing privileges in Windows, has some interesting results for organisations that have made the switch to Windows 7. The key finding shows that 90 percent of critical Windows 7 vulnerabilities could be mitigated simply by not allowing standard users to run with administrator privileges.
Windows 7, like its predecessor Windows Vista, has a variety of security features and controls that do not exist in Windows XP. Features like tighter control of access to the system kernel, DEP (data execution prevention), ASLR (address space layout randomisation), and MIL (mandatory integrity levels)
None of these security controls is a "silver bullet" defense by itself. However, ASLR combined with other security functions such as DEP, and the security aspects of UAC (User Account Control) help Windows 7 (and Windows Vista) to defend itself against many threats that would work on Windows XP and other prior operating systems.
Don't confuse "more secure" with "impervious", though. At the recent Pwn2Own competition, a security researcher was able to circumvent the ASLR and DEP security measures and exploit a flaw in Internet Explorer 8 to take control of the target Windows 7 machine.
However, as the BeyondTrust study indicates, even if an attacker can get past the Windows 7 defenses, most malicious code can be stopped in its tracks just by ensuring that the user is not running as an administrator. The reason is that malicious code generally runs with the rights and privileges of the logged in user, so running as a standard user will restrict the malicious code to running under the standard user context, rendering it unable to attack critical system functions.
A press release from BeyondTrust quotes Steve Kelley, EVP of corporate development, "Enterprises continue to face imminent danger from zero-day attacks as new vulnerabilities are exploited before patches can ever be developed and deployed. Our findings reflect the critical role that restricting administrator rights, plays in protecting against these types of threats. As companies migrate to Windows 7 they need to be aware that despite enhanced security features on the new operating systems, better controls for administrative rights are still needed to provide adequate protection."
The BeyondTrust study also found that removing administrator privileges can mitigate 94 percent of all Internet Explorer vulnerabilities (100 percent on Internet Explorer 8), 100 percent of all Microsoft Office vulnerabilities, and 64 percent of all Microsoft vulnerabilities reported in 2009.
This shouldn't come as any real surprise to most IT administrators. Security experts have repeated the mantra of not letting standard users run with administrator privileges since malware has existed. What has changed, though, is that Microsoft has listened to feedback from the field regarding the issues encountered by customers when configuring workers as standard users, and has implemented changes to address those concerns.
You can expect user backlash, especially from executive level management who prefer to have godlike powers to install and remove whatever software they choose on the system. However, setting aside the broader legal and security issues, as well as the complexity of user support, introduced by letting users have administrator privileges, the bottom line is that simply changing Windows 7 systems to run as standard users can prevent nearly two-thirds of the potential attacks.
Wouldn't you have much more time for more proactive and important tasks, and wouldn't you sleep better at night, by implementing this one simple change?