August 16, 2002, 10:37 AM — Microsoft Corp. Thursday released a patch for a vulnerability it called "critical" that could allow an attacker to take complete control of Windows 2000 systems. The company also released a cumulative patch for SQL Sever 7.0 and 2000 that repaired a new security hole.
The first vulnerability exists in the Network Connection Manager (NCM) component of Windows 2000, which is used to process and handle network connections made by users. The NCM is supposed to run in the user's security context, which usually limits what actions a user can take on the system. Due to the flaw, however, it can run in the LocalSystem context, giving the NCM greater privileges, Microsoft said in its security alert.
When the NCM is used, one of its functions is to call on a handler routine run by the NCM, the Redmond, Washington, company said. The flaw could allow attackers who do not have proper access privileges to create their own handler routine and cause the NCM to run it by creating a network connection, the company said.
This attack could cause the attacker-supplied code to run with full system privileges, giving the attacker control of the machine, Microsoft said.
The vulnerability is mitigated, however, because a user usually needs to have privileges to log on to the target system in order to be able to exploit the flaw, the company said.
More information about the vulnerability, and the patch to fix it, are available at http://www.microsoft.com/technet/treeview/default.asp?url=/technet/security/bulletin/ms02-042.asp.
Microsoft Thursday also released a cumulative patch for SQL Server 7.0 and 2000 that included a fix for a previously undisclosed vulnerability.
The vulnerability exists in the Microsoft-supplied stored procedures that ship with the software and are used for various helper functions, the company said. A flaw in the permissions associated with the procedures could allow users without the proper access rights to execute the procedures with administrator privileges, the company said.
Though Microsoft only rates the flaw as "moderate," an attacker could exploit the flaw in order to make database calls they are not permitted to make, the company said.
The full cumulative patch, as well as information on the new vulnerability, can be found at http://www.microsoft.com/technet/treeview/default.asp?url=/technet/security/bulletin/MS02-043.asp.