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-------------------------- NSOADV-2011-003 ---------------------------
Majordomo2 'help' Command Directory Traversal (Patch Bypass)
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Title: Majordomo2 'help' Command Directory Traversal
Severity: Medium
Advisory ID: NSOADV-2011-003
CVE: CVE-2011-0063
Found Date: 03.02.2011
Date Reported: 03.02.2011
Release Date: 19.02.2011
Author: Nikolas Sotiriu
Mail: nso-research at sotiriu.de
Website: http://sotiriu.de/
Twitter: http://twitter.com/nsoresearch
Advisory-URL: http://sotiriu.de/adv/NSOADV-2011-003.txt
Vendor/Project: http://www.mj2.org/
Affected Products: majordomo2 <= 20110203
Remote Exploitable: Yes
Local Exploitable: No
Patch Status: Vendor released a patch (See Solution)
Discovered by: Nikolas Sotiriu
Disclosure Policy: http://sotiriu.de/policy.html
Thanks to: Thierry Zoller: For the permission to use his
Policy
Background:
===========
Majordomo 2 is an upwardly-compatible rewrite of the popular majordomo
mailing list manager software by Jason Tibbitts and Michael Yount.
Description:
============
Majordomo2 <= 20110203 is affected by a Directory Traversal
vulnerability due to parameter 'extra' of the 'help' command in the
function '_list_file_get()' is not properly sanitized.
The original bug was made public on 03.02.2011 by Michael Brooks
of sitewat.ch:
https://sitewat.ch/en/Advisory/View/1
https://bugzilla.mozilla.org/show_bug.cgi?id=628064
I discovered, that the patch, which is in the CVS since version 20110125
don't protect against the Directory Traversal bug.
https://bug628064.bugzilla.mozilla.org/attachment.cgi?id=506481
The diff build in the regex '$file =~ s!/?\.\./?!!g;', which deletes
'../' from $file. Bypassing this regex is quiet simple by using './.../'
insted '../'.
Proof of Concept :
==================
HTTP:
http://<target>/cgi-bin/mj_wwwusr?passw=&list=GLOBAL&user=&func=help&
extra=./..././..././..././..././..././..././..././.../etc/passwd
SMTP:
help ./..././..././..././..././..././..././..././.../etc/passwd
Solution:
=========
Update to Majordomo2 >= 20110204
http://ftp.mj2.org/pub/mj2/snapshots/2011-02/majordomo-20110204.tar.gz
References:
===========
Sitewatch Advisory: https://sitewat.ch/en/Advisory/View/1
Original Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=628064
Patch Bypass: https://bugzilla.mozilla.org/show_bug.cgi?id=631307
Disclosure Timeline (YYYY/MM/DD):
=================================
2011.02.03: Patch bypass vulnerability found
2011.02.03: Informed security [at] mozilla.org
2011.02.03: Mozilla opend Bug 631307 in bugzilla
2011.02.03: Jason Tibbitts comitted a fix (Sorry again)
2011.02.04: Snapshot available for download
2011.02.04: Discuss the public disclosure
2011.03.04: Got the Bug Bounty Money
2011.03.08: Release of Advisory
