[NEWS] Mac OS X HFS+ Multiple Vulnerabilities (__Fork)

From: SecuriTeam (support_at_securiteam.com)
Date: 02/21/05

  • Next message: SecuriTeam: "[TOOL] NMB Scanner - SMB and NMB Protocol Scanner"
    To: list@securiteam.com
    Date: 21 Feb 2005 12:54:19 +0200
    
    

    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

    - - - - - - - - -

      Mac OS X HFS+ Multiple Vulnerabilities (__Fork)
    ------------------------------------------------------------------------

    SUMMARY

    Hierarchical File System Plus(HFS+) is "a file system developed by Apple
    Computer for use on computers running Mac OS".

    HFS+ allow servers such as Apache to retrieve the source of a PHP or JSP
    source files using the data and resource fork options.

    DETAILS

    Vulnerable Systems:
     * MacOS X version 10.2 and above

    Apple's HFS and HFS+ file systems allows two separate data streams for
    each file, referred to as the "data fork" and "resource fork". The classic
    Mac OS operating systems and Carbon API on Mac OS X provide separate
    functions for opening and manipulating the data and resource forks. In Mac
    OS X, however, support for addressing these separate streams has been
    integrated into the POSIX API. In Mac OS X 10.2 and above, opening the
    file by its pathname opens the data fork, but the data fork or resource
    fork may also be opened for a given file by respectively appending
    "/..namedfork/data" or "/..namedfork/rsrc" to the pathname passed to the
    open(2) system call. In previous versions, they may be addressed by
    appending the special pathnames "/.__Fork/data" or "/.__Fork/rsrc". The
    resource fork may also be opened in most versions of Mac OS X by appending
    "/rsrc" to the file pathname.

    Due to this feature being available throughout the operating system, via
    the POSIX API, it is therefore available to any software involved in the
    opening of file streams via the open() syscall, such as a web server
    opening an HTML or PHP file present on the Darwin servers file system. As
    a result, server daemons, such as web servers which open file streams,
    based on user controlled data, may be fooled into opening the respective
    files resource and/or file fork rather than the absolute file name. This
    may allow users to view arbitrary data, such as the source code of server
    interpreted documents (such as PHP and JSP files).

    Workaround:
    The HFS+ file system is not recommended for dedicated servers, but is
    required to support numerous legacy Macintosh applications. At the time of
    this technical advisory, it is strongly recommended that organizations
    with public Internet-facing Apple servers consider migration to the
    Berkeley Fast File System (FFS/UFS) option available in OS X.

    ADDITIONAL INFORMATION

    The information has been provided by <mailto:tac@netsec.net> TAC.

    ========================================

    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.


  • Next message: SecuriTeam: "[TOOL] NMB Scanner - SMB and NMB Protocol Scanner"