Multiple Windows XP Kernel Vulnerability Allow User Mode Programs To Gain Kernel Privileges
There exist several vulnerabilities in one of Windows XP kernel's native API functions which allow any user with the SeDebugPrivilege privilege to execute arbitrary code in kernel mode, and read from and write to any memory address, including kernel memory
More details at http://www.securiteam.com/windowsntfocus/5TP0B2KC0K.html
Also published in http://www.securitytracker.com/alerts/2004/Feb/1009128.html but the editor noted:
A user has reported to us and the author of the original message has confirmed that a user with SeDebugPrivilege rights can, by the intended design of the associated privileges, modify the address space of arbitrary processes. As such, the behavior described below does not provide the user with any greater privileges than the user would already have. We will delete this entry from our database shortly

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