IIS 5.0 allows viewing files using %3F+.htr

Georgi Guninski security advisory #33, 2001

IIS 5.0 allows viewing files using %3F+.htr

Systems affected:
IIS 5.0 patched against the file fragment reading vulnerability

Risk: Medium
Date: 8 January 2001

Legal Notice:
This Advisory is Copyright (c) 2000 Georgi Guninski. You may distribute it unmodified.
You may not modify it and distribute it or distribute parts of it without the author's
written permission.

Disclaimer:
The opinions expressed in this advisory and program are my own and not of any company.
The usual standard disclaimer applies, especially the fact that Georgi Guninski
is not liable for any damages caused by direct or indirect use of the information
or functionality provided by this advisory or program.
Georgi Guninski bears no responsibility for content or misuse of this advisory or program or
any derivatives thereof.

Description:

IIS 5.0 allows viewing most types of CGI files if a special request is performed.

Details:
The following URL:

http://TARGETIIS/scripts/test.pl%3F+.htr

reveals the content of /scrips/test.pl instead of executing it.
This may giveway passwords in CGI and other stuff.
If you are not patched the following may work (not discovered by me):
http://TARGETIIS/scripts/test.pl+.htr
This does not work for some types of .ASP if they contain certain characters.

Vendor status:
Microsoft was contacted on 4 January 2001.

Regards,
Georgi Guninski
http://www.guninski.com