Vulnerability Note VU#814644

Microsoft Remote Access Connection Manager service vulnerable to buffer overflow

RRAS makes it possible for a computer to function as a network router. RRAS also provides the next generation of server functionality for the Remote Access Service (RAS) for Windows. The RRAS server functionality follows and builds upon the Remote Access Service (RAS) that was included in previous operating systems.

The Remote Access Service lets users connect to a remote computer over phone lines, so they can work as if their system were physically connected to the remote network. These services enable remote users to do activities such as send and receive e-mail, fax documents, retrieve files, and print documents on an office printer.
The Remote Access Service is a native service in Windows 2000, Windows XP and Windows Server 2003.

On Windows 2000 Service Pack 4 and Windows XP Service Pack 1, any anonymous user who could deliver a specially crafted message to the affected system could try to exploit this vulnerability. In order to exploit the vulnerability on Windows XP Service Pack 2 and Windows Server 2003, an attacker must have valid login credentials to a target system.

Microsoft has published patches for this issue in Microsoft Security Bulletin MS06-025.

Workarounds

In addition to the patches, Microsoft has also published a number of workarounds for this issue in Microsoft Security Bulletin MS06-025. Users, particularly those who are unable to apply the patch, are encouraged to implement these workarounds.

Systems Affected

http://www.microsoft.com/technet/security/bulletin/ms06-025.mspx
http://www.ngssoftware.com/advisories/rasman.txt

Credit

Thanks to Microsoft for reporting this vulnerability. Microsoft, in turn, credits Peter Winter-Smith of NGS Software with reporting this vulnerability to them.

This document was written by Chad R Dougherty.

Other Information

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