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Credit:
The information has been provided by Microsoft Product Security.
The original article can be found at: http://www.microsoft.com/technet/security/bulletin/ms08-005.mspx
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Affected Software
Operating System - Component - Maximum Security Impact - Aggregate Severity Rating - Bulletins Replaced by this Update
* Microsoft Windows 2000 Service Pack 4 - Microsoft Internet Information Services 5.0 - Elevation of Privilege - Important - None
* Windows XP Professional Service Pack 2 - Microsoft Internet Information Services 5.1 - Elevation of Privilege - Important - None
* Windows XP Professional x64 Edition and Windows XP Professional x64 Edition Service Pack 2 - Microsoft Internet Information Services 5.1 - Elevation of Privilege - Important - None
* Windows Server 2003 Service Pack 1 and Windows Server 2003 Service Pack 2 - Microsoft Internet Information Services 6.0 - Elevation of Privilege - Important - None
* Windows Server 2003 x64 Edition and Windows Server 2003 x64 Edition Service Pack 2 - Microsoft Internet Information Services 6.0 - Elevation of Privilege - Important - None
* Windows Server 2003 with SP1 for Itanium-based Systems and Windows Server 2003 with SP2 for Itanium-based Systems - Microsoft Internet Information Services 6.0 - Elevation of Privilege - Important - None
* Windows Vista - Microsoft Internet Information Services 7.0 - Elevation of Privilege - Important - None
* Windows Vista x64 Edition - Microsoft Internet Information Services 7.0 - Elevation of Privilege - Important - None
Non-Affected Software
* Windows Vista Service Pack 1 (all editions)
* Windows Server 2008 (all editions)
File Change Notification Vulnerability - CVE-2008-0074
A local elevation of privilege vulnerability exists in the way that the Internet Information Service handles file change notifications in the FTPRoot, NNTPFile\Root, and WWWRoot folders. An attacker who successfully exploited this vulnerability could execute arbitrary code in the context of local system. An attacker could then install programs; view, change, or delete data; or create new accounts with full administrative rights.
CVE Information:
CVE-2008-0074
Mitigating Factors for File Change Notification Vulnerability - CVE-2008-0074
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
* On Windows XP Professional Service Pack 2 and Windows Server 2003, the IUSR_MACHINENAME account (used for anonymous access) does not have write access to the WWW root folders by default.
* The specially crafted file or folder that would be required to exploit this vulnerability must be created locally. It could not be created through an FTP client connected to the FTP server service.
* On Windows XP, Windows Server 2003, and Windows Vista, IIS is not installed or enabled by default.
Workarounds for File Change Notification Vulnerability - CVE-2008-0074
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
* On Windows Server 2003, stop the FTP and NNTP services
Exploitation of this vulnerability would require that the attacker have write access to the FTP root or NNTP root folders. By default the IIS anonymous access account, IUSR_MACHINENAME, has write access to the FTP root and NNTP root folders. Stopping these services will prevent the FTP and NNTP services from responding to change notifications for files in those directories. To stop the FTP and NNTP services, follow these steps:
From a command prompt, run the following commands:
net stop msftpsvc
net stop nntpsvc
Impact of workaround.Users will be unable to use the FTP and NNTP services.
How to undo the workaround.To undo the workaround, follow these steps:
From a command prompt, run the following commands:
net start msftpsvc
net start nntpsvc
* Deny write access to the NNTP root, FTP root, and WWW root folders for any accounts that are used to execute user controlled ASP pages.
Verify that the WWW root folder does not allow write access for any accounts used to execute user controlled ASP pages. To deny write access to the NNTP root, FTP root, and WWW root folders follow these steps:
Note The ACLs of the WWW root folder should be verified to ensure that anonymous access user accounts do not have write access.
Note The following commands will deny the IIS anonymous user account write access to the default FTP and NNTP root directories of a machine named WS2003ENTSP1.
From a command prompt, run the following commands:
cacls c:\inetpub\ftproot /E /P IUSR_WS2003ENTSP1:R
cacls c:\inetpub\ftproot /E /P USERS:R
cacls c:\inetpub\nntpfile\root /E /P "ANONYMOUS LOGON":R
cacls c:\inetpub\nntpfile\root /E /P EVERYONE:R
Impact of workaround.Users will be denied write access to the NNTP root, FTP root, and WWW root folders for any accounts that are used to execute user-controlled ASP pages.
How to undo the workaround. Restore the ACLs on the folders to their previously configured setting.
FAQ for File Change Notification Vulnerability - CVE-2008-0074
What is the scope of the vulnerability?
This is a local elevation of privilege vulnerability. An attacker who successfully exploited this vulnerability could execute arbitrary code in the context of local system.
What causes the vulnerability?
The vulnerability exists in the way that the Internet Information Service handles the file change notifications in the FTPRoot, NNTPFile\Root, and WWWRoot folders.
What might an attacker use the vulnerability to do?
A local attacker could successfully exploit this vulnerability to gain full control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full administrative rights.
How could an attacker exploit the vulnerability?
A local attacker would have to be able to create or modify a file only in the FTPRoot, NNTPFile\Root, or WWWRoot directory. Virtual directories and sub-directories are not affected. A remote attacker would have to be able to upload a script to an affected IIS server, and be able to run the script. This uploaded script would need write access to the FTPRoot, NNTPFile\Root, or WWWRoot folders.
What systems are primarily at risk from the vulnerability?
Web hosting providers that allow their customers to upload ASP pages to their hosted web sites are primarily at risk from exploitation of this vulnerability. In addition, Microsoft Windows 2000 Service Pack 4 systems running IIS 5.0 are at risk from this vulnerability because IIS is enabled by default. Supported editions of Windows XP, Windows Server 2003, and Windows Vista are also at risk if the service is enabled.
What does the update do?
The update removes the vulnerability by modifying the way that the Internet Information Service handles file change notifications in the FTPRoot, NNTPFile\Root, and WWWRoot folders.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure. Microsoft had not received any information to indicate that this vulnerability had been publicly disclosed when this security bulletin was originally issued.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers and had not seen any examples of proof of concept code published when this security bulletin was originally issued.
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