Title: Index Server Search Function Contains Unchecked Buffer
Date: 10 May 2001
Software: Index Server 2.0, Indexing Service for Windows 2000
Impact: Run code of attacker's choice; file disclosure
Bulletin: MS01-025
Microsoft encourages customers to review the Security Bulletin at:
http://www.microsoft.com/technet/security/bulletin/MS01-025.asp.
The patches provided in the bulletin address two security
vulnerabilities that are unrelated to each other except in the sense
that both affect Index Server 2.0. The first vulnerability is a
buffer overrun vulnerability. Index Server 2.0 has an unchecked
buffer in a function that processes search requests. If an overly
long value were provided for a particular search parameter, it would
overrun the buffer. If the buffer were overrun with random data, it
would cause Index Server to fail. If it were overrun with carefully
selected data, code of the attacker's choice could be made to run on
the server, in the Local System security context.
The second vulnerability affects both Index Server 2.0 and Indexing
Service in Windows 2000, and is a new variant of the "Malformed
Hit-Highlighting" vulnerability discussed in Microsoft Security
Bulletin MS00-006
(http://www.microsoft.com/technet/security/bulletin/MS00-006.asp).
The new variant has almost the same scope as the original
vulnerability, but potentially exposes a new file type If an attacker
provided an invalid search request, she could read "include" files
residing on the web server. The new patch eliminates all known
variants of the vulnerability.
Index Server 2.0 buffer overrun:
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