While Microsoft labors to produce an apex of security with its Windows Vista operating system, Symantec has put the code under the microscope and has issued a report in which it claims that the security level of Microsoft's latest OS product will deliver an inferior security level to XP. Symantec claims that it has identified several security vulnerabilities related to Vista's networking technology that will cause the instability of the system.

"Microsoft has removed a large body of tried and tested code and replaced it with freshly written code, complete with new corner cases and defects," Symantec researchers wrote in the report. "This may provide for a more stable networking stack in the long term, but stability will suffer in the short term."

Symantec's tiered analysis took into consideration the link, network, transport, and session layers and revolved around stability issues, undocumented protocols and behaviors and new protocols (LLTD, IPv6, Teredo, SMB2), and encapsulation.

"Symantec evaluated the security of the network stack of public pre-release versions of Microsoft's Windows Vista operating system. Our investigation was broad and shallow, aiming to provide timely intelligence on the new system by covering as many aspects of the network stack as was practical in a small amount of time. Because of the limited amount of time given to the project, our analysis did not penetrate very deeply into any one aspect of the network stack and was forced to omit some key components. We performed our analysis on the public beta builds 5231, 5270, and 5384 of Windows Vista. Since Windows Vista is still a work in progress, we expect many of our results to be invalidated by changes made prior to its public release," stated Symantec in its report.