A hacker picking apart the security model of Microsoft’s brand new Windows Server 2008 has found serious design weaknesses that render some of the product’s new security protections “useless.”
Cesar Cerrudo, founder and Chief Executive Officer of Argeniss Information Security, in Parana, Argentina, says the weaknesses could lead to privilege escalation attacks opens the door for a skilled hacker to take complete control of the operating system.
“[We found] from design issues that were not identified by Microsoft engineers during the Security Development Lifecycle, and allows accounts commonly used by Windows services-NETWORK SERVICE and LOCAL SERVICE-to bypass new Windows services protection mechanisms and elevate privileges, Cerrudo said.
He said the discovery also affects Internet Information Services 7 in the default configuration, allowing ASP.NET applications to “completely compromise” operating system security.
Cerrudo, a security researcher who is highly regarded for his work on database security, said the problem also afects Windows Vista, Windows XP and Windows 2003.
“On Windows XP and Windows 2003 the problem is especially severe since any Windows service, even when running under a low privileged account, can potentially break through the security protections and fully compromise the operating system. This includes all web applications deployed on Internet Information Services 6,” he added.
Cerrudo declined to provide technical details of the attack scenarios. He plans to discuss the issue at the upcoming Hack in the Box Conference in Dubai, United Arab Emirates.
In that talk, entitled Token Kidnapping, Cerrudo said he will explain how it is possible in Windows XP and 2003 to elevate privileges to LOCAL SYSTEM from any process that has impersonation rights.
Vulnerable, but Still an Improvement
In Windows Vista and Windows 2008, he plans to show how to elevate privileges to LOCAL SYSTEM from processes running under NETWORK SERVICE and LOCAL SERVICE accounts.
At the Hack in the Box conference, Cerrudo said he will demonstrate zero-day code for elevating privileges in SQL Server and Microsoft’s Internet Information Services.
Even as he set out to pour cold water on the design weaknesses, Cerrudo said his audit found that Windows Server 2008 was “generally more secure than previous versions.”
Microsoft has touted Windows Server 2008 as its “most secure server” to date, featuring architectural and defense-in-depth protections similar to those fitted into Windows Vista.
The operating system has been hardened to help protect against failure and several new technologies help prevent unauthorized connections to networks, servers, data, and user accounts.
It comes with NAP (Network Access Protection) to handle health checks; enhancements to make Active Directory services a unified and integrated IDA (Identity and Access) solution; and (RODC) Read-Only Domain Controller and BitLocker Drive Encryption to allow users to securely deploy Active Directory databases.