Security Identity Mapping format is not homogeneous with the Schannel certificate mapper format in Windows Server 2003

Security Identity Mapping uses a specific format to store the Issuer name and the Subject name in the AltSecurityIdenties property. This format and the format that is used in the Schannel certificate mapper are not homogeneous. This format inconsistency may cause certificate-based authentication to fail.

The Schannel authentication may fail if the certificate that is used for the name mapping contains a plus character (+) either in the Issuer or in the Subject part. For example, if the following *.cer file contains a plus character in the AltSecurityIdenties property that is used for name mappings, the Schannel authentications based on this certificate will fail: The Schannel certificate mapper expects the following string (without the plus character) in the AltSecurityIdenties property: This problem occurs because the Microsoft Management Console (MMC) snap-in that creates the mapping does not use the same format (logic) that is used by the SSL handshake when the Schannel authentication tries to map the certificate to a user.

Hotfix Information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

No prerequisites are required.

Restart requirement

You must restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

To work around this problem, use a custom script to set the X509 AltSecurityIdentities property for the user account. Do not use the MMC snap-in.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section of this article.

The AltSecurityIdentities property is a multivalued property that contains mappings for X509 certificates or external Kerberos user accounts for authentication. Various security packages, including public key authentication packages and Kerberos, use this information to authenticate users who present an alternative form of identification (such as certificate or Unix Kerberos ticket). These security packages build a Windows 2000 token based on the alternative form of identification so that the user can access system resources.

For X509 certificates, the values must be the Issuer name and the Subject name in 509v3 certificates that are issued by an external public Certification Authority. These names map to the user account that is used to find an account for authentication. The Schannel package uses the following syntax:



For more information about user security attributes and the AltSecurityIdenties property, visit the following MSDN Web page: For additional information, click the following article number to view the article in the Microsoft Knowledge Base: