Microsoft Security Bulletin MS08-067(KB958644)

2008年11月4日 | 分类: 信息安全 | 标签: , , ,

This security update resolves a privately reported vulnerability in the Server service. The vulnerability could allow remote code execution if an affected system received a specially crafted RPC request. On Microsoft Windows 2000, Windows XP, and Windows Server 2003 systems, an attacker could exploit this vulnerability without authentication to run arbitrary code. It is possible that this vulnerability could be used in the crafting of a wormable exploit. Firewall best practices and standard default firewall configurations can help protect network resources from attacks that originate outside the enterprise perimeter.
This security update is rated Critical for all supported editions of Microsoft Windows 2000, Windows XP, Windows Server 2003, and rated Important for all supported editions of Windows Vista and Windows Server 2008. For more information, see the subsection, Affected and Non-Affected Software, in this section
The security update addresses the vulnerability by correcting the way that the Server service handles RPC requests. For more information about the vulnerability, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.Recommendation. Microsoft recommends that customers apply the update immediately

More detail about MS08-067, the out-of-band netapi32.dll security update
An unauthenticated attacker can trigger this vulnerability remotely for code execution on Windows Server 2000, Windows XP and Windows 2003. By default, Windows Vista and Windows Server 2008 require authentication. However, the attacker must be able to reach the RPC interface to exploit the vulnerability. In the default out-of-the-box scenario, the interface is not reachable due to the Windows firewall enabled by default on Windows XP SP2, Windows Vista, and Windows Server 2008. Unfortunately, either one of the following two conditions exposes the RPC endpoint:
1) Windows firewall is disabled
2) Windows firewall is enabled but file/printer sharing is also enabled.
When File/Printer Sharing is enabled on Windows Vista and Windows Server 2008, the Windows firewall only expose the RPC interface to the network type shared. For example, if a printer is shared on a network type ‘Private’, the Windows firewall will block incoming RPC connections if the computer switches over to a network type ‘Public’. If you then choose to share the printer on the network type ‘Public’, Vista and Windows Server 2008 will prompt to ask if you really want to enable “File and Printer Sharing” for ALL public networks.
For more information about file/printer sharing, visit the following URLs:
– for Vista
– for XP
The following picture illustrates the risk for each platform in more detail