Outlook Web Access authentication bypass

[Chris Robertson]

This exploit exhibits the same symptoms as CAN-2002-0507 however I have
found it is possible on an Exchange 5.5 (patches current to within ~3
months) single system Outlook Web Access install (IIS and Exchange on the
same server) to access any mailbox once the client has been successfully
authenticated in Netscape 7.0 on Windows 2k and Redhat 7.2, Mozilla 1.0.1,
Galeon 1.2.5, and Konqueror 3.0.3-13 on Redhat 8.0. Additionally under IE
5.50.4807.2300 it is possible to get the same behavior by canceling an
attempted login to a non-authorized mailbox and editing the url from
...."isnewwindow=0"... to ..."isnewwindow=1"...

Does anyone have anymore info on this?

Thanks,
Chris Robertson
Security Engineer
Instill Corp.

[Chris Robertson]

Please disregard this. A configuration change had been unknowingly made on
the Exchange server (making the test account an Exchange Admin).

I sincerly apologize for any confusion this may have caused.

Chris Robertson

-----Original Message-----
From: Chris Robertson [mailto:Chris.Robertson@instill.com]
Sent: Friday, May 23, 2003 1:03 AM
To: 'bugtraq@securityfocus.com'
Subject: Outlook Web Access authentication bypass


This exploit exhibits the same symptoms as CAN-2002-0507 however I have
found it is possible on an Exchange 5.5 (patches current to within ~3
months) single system Outlook Web Access install (IIS and
Exchange on the
same server) to access any mailbox once the client has been successfully
authenticated in Netscape 7.0 on Windows 2k and Redhat 7.2,
Mozilla 1.0.1,
Galeon 1.2.5, and Konqueror 3.0.3-13 on Redhat 8.0.
Additionally under IE
5.50.4807.2300 it is possible to get the same behavior by canceling an
attempted login to a non-authorized mailbox and editing the url from
...."isnewwindow=0"... to ..."isnewwindow=1"...

Does anyone have anymore info on this?

Thanks,
Chris Robertson
Security Engineer
Instill Corp.