Perimeter E-Security customers should be aware of a Microsoft Windows XP and Server 2003 exploit. Exploit code has been posted online that shows attackers exactly how to compromise Windows XP and Server 2003 operating systems remotely. This is possible due to a newly discovered security flaw in the way Windows Help and Support Center process links. These systems are supposed to work based on a fixed “whitelist” (a list of approved and authorized URLs), however a security researcher at Google has shown how cyber criminals can add URLs to that whitelist. As a result, an attacker could trick a user into following a link which could download any file the hacker would like. The link and downloaded files can use the same permissions as the systems current user. Many systems are configured by default with the user having administrative privileges.
Microsoft said “Given the public disclosure of the details of the vulnerability, and how to exploit it, customers should be aware that broad attacks are likely,” this includes worms and a host of other malware that can automatically exploit this code through a variety of methods.
This is worse than most vulnerabilities we see. Most vulnerabilities allow the system to be compromised in a specific way that may allow limited access or flexibility to the hacker. This vulnerability makes it very easy for the cyber criminal to install any software they want as if they are the system administrator.
The solution?
- There is no automated fix from Microsoft at this time. However, there is a manual ”work around.”
The manual “work around” involves editing the Registry. Note – only experienced system administrators should manually edit the registry. One wrong move can cause major stability and bootup problems. The details for the registry edit can be found in the Microsoft Security Advisory (2219475).
Beware that Microsoft says that this may break links that you are trying to use in the Help and Support Center. Microsoft has also posted a knowledge base article with a “fixit” here.
- Stay tuned for more details from Microsoft
Microsoft is working on a patch. The Google researcher who discovered the flaw has released a fix; however, Microsoft says that this fix is easily bypassed and that users should not rely on the Google fix to resolve the problem.
While Microsoft is working on a patch, Perimeter E-Security continues to encourage users (especially those using XP) to create a limited user account for everyday computing. Read more on this here. This will go a long way to protect systems from this exploit as well as many others we have seen in the past and will likely see in the future.
Contact us today at 800.234.2175 to talk with a security expert if you have further questions.
Tags: Windows XP exploit, Server 2003 exploit, vulnerability assessment tools, IT security, application penetration testing, managed service providers, intrusion detection system, security penetration testing