Article ID: 242215
Article Last Modified on 11/1/2006
APPLIES TO
- Microsoft Windows NT version 4.0 Option Pack
This article was previously published under Q242215
SYMPTOMS
Remote Authentication Dial-In User Service (RADIUS) realms and prefixes do not work as per the original design specification.
For example, define a RADIUS realm named "realmname" with an "m/" prefix that grants users logon access only to the mail service. When a dial-up user logs on to the Internet service provider (ISP) as "m/username", RADIUS sees the "m/" prefix and applies the RADIUS profile, which restricts the user account to accessing mail only. The "m/username" logon information is then forwarded to the Microsoft Commercial Internet System (MCIS) Membership server and the user is logged on with the appropriate restrictions.
If, however, the user logs on with an "M/" prefix, the RADIUS server does not apply the "m/" profile because the RADIUS server is case sensitive for realms and prefixes. The RADIUS server also forwards "M/username" to the MCIS Membership server, and the user is successfully logged on without the necessary restrictions. The Membership server successfully authenticates the user because it is case insensitive for prefixes and realms.
Therefore, if a user types a realm and prefix in a different case than was originally defined, the user bypasses the restrictions defined in the profile on the RADIUS server. ISPs have no way to limit user access to the services that they are providing to their users.
RESOLUTION
A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Windows NT 4.0 service pack that contains this hotfix.
To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:
NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.
The English-language version of this fix should have the following file attributes or later:
Date Time Size File name Platform
-------------------------------------------------------------
9/3/99 8:48am 231,680 Authsrv.exe x86
9/3/99 8:49am 347,408 Authsrv.exe Alpha
STATUS
Microsoft has confirmed that this is a problem in Microsoft Windows NT 4.0.
Keywords: kbhotfixserver kbqfe kbbug kbfix kbqfe KB242215
