The following security advisory is sent to the securiteam mailing list, and can
be found at the SecuriTeam web site: http://www.securiteam.com
- - promotion
The SecuriTeam alerts list - Free, Accurate, Independent.
Get your security news from a reliable source.
http://www.securiteam.com/mailinglist.html
- - - - - - - - -
Ruby WEBrick Directory Traversal
------------------------------------------------------------------------
SUMMARY
<http://www.ruby-lang.org/> WEBrick is an HTTP server library written in
Ruby that uses servlets to extend its capabilities. Built into WEBrick are
four servlets, handling CGI, ERb, file directories, and a generic Proc
servlet. Ruby on Rails uses WEBrick as a quick and easy webserver to start
developing your Rails applications. However, for whatever ease of
development WEBrick adds to your application, it is generally considered
not suitable for any production environment. The Ruby WEBrick HTTPd
server has been found to contain a directory traversal security
vulnerability.
DETAILS
Vulnerable Systems:
* Ruby version 1.8.4 and all prior versions
* Ruby version 1.8.5-p114 and all prior versions
* Ruby version 1.8.6-p113 and all prior versions
* Ruby version 1.9.0-1 and all prior version
Immune Systems:
* Ruby version 1.8.5-p115
* Ruby version 1.9.0-2
The following programs are vulnerable:
* Programs that publish files using WEBrick::HTTPServer.new with the
:DocumentRoot option
* Programs that publish files using WEBrick::HTTPServlet::FileHandler
Affected systems are:
1. Systems that accept backslash (\) as a path separator, such as Windows.
2. Systems that use case insensitive filesystems such as NTFS on Windows,
HFS on Mac OS X.
This vulnerability has the following impacts.
1. Attacker can access private files by sending a URL with URL encoded
backslash (\). This exploit works only on systems that accept backslash as
a path separator.
Example:
<http://[server]:[port]/..%5c..%5c..%5c..%5c..%5c..%5c..%5c..%5c..%5c..%5c/boot.ini>
http://[server]:[port]/..%5c..%5c..%5c..%5c..%5c..%5c..%5c..%5c..%5c..%5c/boot.ini
2. Attacker can access files that matches to the patterns specified by the
:NondisclosureName option (the default value is [".ht*", "*~"]). This
exploit works only on systems that use case insensitive filesystems.
Solution:
The vendor has release patches to address this vulnerability, more details
can be found here:
<http://www.ruby-lang.org/en/news/2008/03/03/webrick-file-access-vulnerability/>
File access vulnerability of WEBrick
ADDITIONAL INFORMATION
The information has been provided by <mailto:alexandr.polyakov@dsec.ru>
Alexandr Polyakov.
========================================
This bulletin is sent to members of the SecuriTeam mailing list.
To unsubscribe from the list, send mail with an empty subject line and body to:
list-unsubscribe@securiteam.com
In order to subscribe to the mailing list, simply forward this email to:
list-subscribe@securiteam.com
====================
====================
DISCLAIMER:
The information in this bulletin is provided "AS IS" without warranty of any
kind.
In no event shall we be liable for any damages whatsoever including direct,
indirect, incidental, consequential, loss of business profits or special
damages.
