Original issue date: December 5, 1997<BR>
Last revised: March 08, 1999<BR>
Updated patch information for Sun Microsystems

<P>A complete revision history is at the end of this file.

   The text of this advisory was originally released on December 5, 1997, as
   AA-97.29, developed by the Australian Computer Emergency Response Team. To
   more widely broadcast this information, we are reprinting the AUSCERT
   advisory here with their permission. Only the contact information at the
   end has changed: AUSCERT contact information has been replaced with CERT/CC
   contact information.

<P>We will update this advisory as we receive additional information.
   Look for it in an "Updates" section at the end of the advisory.


AUSCERT has received information that a vulnerability exists in the
statd(1M) program, available on a variety of Unix platforms.

<P>This vulnerability may allow local users, as well as remote users to gain
root privileges.

<P>Exploit information involving this vulnerability has been made publicly

<P>This vulnerability is different to the statd vulnerability described
in CERT/CC advisory <A HREF="http://www.cert.org/advisories/CA-96.09.rpc.statd.html">CA-96.09</A>.

<P>The vulnerability in statd affects various vendor versions of statd.
AUSCERT recommends that sites take the steps outlined in section 3 as soon
as possible.

<P>This advisory will be updated as more information becomes available.


<H2>I. Description</H2>

    AUSCERT has received information concerning a vulnerability in some
    vendor versions of the RPC server, statd(1M).

<P>statd provides network status monitoring.  It interacts with lockd to
    provide crash and recovery functions for the locking services on NFS.

<P>Due to insufficient bounds checking on input arguments which may be
    supplied by local users, as well as remote users, it is possible to
    overwrite the internal stack space of the statd program while it is
    executing a specific rpc routine.  By supplying a carefully designed
    input argument to the statd program, intruders may be able to force
    statd to execute arbitrary commands as the user running statd.  In most
    instances, this will be root.

<P>This vulnerability may be exploited by local users.  It can also be
    exploited remotely without the intruder requiring a valid local account
    if statd is accessible via the network.

<P>Sites can check whether they are running statd by:

<P>On system V like systems:
<PRE>        # ps -fe |grep statd
        root   973     1  0 14:41:46 ?        0:00 /usr/lib/nfs/statd
        On BSD like systems:
<PRE>        # ps -auxw |grep statd
        root       156  0.0  0.0   52    0 ?  IW   May  3  0:00 rpc.statd
    Specific vendor information regarding this vulnerability can be found
    in Section III.

<H2>II. Impact</H2>

   This vulnerability permits attackers to gain root privileges.  It can
    be exploited by local users.  It can also be exploited remotely without
    the intruder requiring a valid local account if statd is accessible
    via the network.

<H2>III.  Workarounds/Solution</H2>

    The statd program is available on many different systems.  As vendor
    patches are made available sites are encouraged to install them
    immediately (Section 3.1).

<P>If you are not using NFS in your environment then there is no need
    for the statd program to be running and it can be disabled (Section

<H3>3.1 Vendor information</H3>

    The following vendors have provided information concerning the
    vulnerability in statd.
	Data General Corporation<BR>
        Digital Equipment Corporation<BR>
        IBM Corporation<BR>
        The NetBSD Project<BR>
        Red Hat Software<BR>
        Sun Microsystems<BR>

    Specific vendor information has been placed in Appendix A.

<P>If the statd program is required at your site and your vendor is not
    listed, you should contact your vendor directly.

<P>If you do not require the statd program then it should be disabled
    (Section 3.2).

<H3>3.2 Disabling statd</H3>

    The statd daemon is required as part of an NFS environment.  If you
    are not using NFS there is no need for this program and it can be
    disabled.  The statd (or rpc.statd) program is often started in the
    system initialisation scripts (such as /etc/rc* or /etc/rc*.d/*).
    If you do not require statd it should be commented out from the
    initialisation scripts.  In addition, any currently running statd
    should be identified using ps(1) and then terminated using kill(1).


<H2>Appendix A  Vendor information</H2>

The following information regarding this vulnerability for specific vendor
versions of statd has been made available to AUSCERT.  For additional
information, sites should contact their vendors directly.


No versions of BSD/OS are vulnerable to this problem.

<H4>Data General Corporation</H4>

This problem is under investigation.

<H4>Digital Equipment Corporation</H4>

"DIGITAL UNIX  rpc.statd V3.2g, V4.0, V4.0a, V4.0b, V4.0c, V4.0d"
was issued April 30, 1998. For more information, please see

    the World Wide Web at the following FTP address:


    Use the FTP access option, select DIGITAL_UNIX directory
    then choose the appropriate version directory 
    and download the patch accordingly.


HP is not vulnerable.

<H4>IBM Corporation</H4>
AIX 3.2 and 4.1 are vulnerable to the statd buffer overflow.  However,
the buffer overflow described in this advisory was fixed when the APARs
for CERT CA-96.09 was released.  See the appropriate release below to
determine your action.

        AIX 3.2
        Apply the following fix to your system:

            APAR - IX56056 (PTF - U441411)

        To determine if you have this PTF on your system, run the following

            lslpp -lB U441411

        AIX 4.1
        Apply the following fix to your system:

            APAR - IX55931

        To determine if you have this PTF on your system, run the following

            instfix -ik IX55931

        Or run the following command:

            lslpp -h bos.net.nfs.client

        Your version of bos.net.nfs.client should be or later.

        AIX 4.2
        No APAR required.  Fix already contained in the release.

        APARs may be ordered using Electronic Fix Distribution (via
        FixDist) or from the IBM Support Center.  For more information on
        FixDist, reference URL:


        or send e-mail to aixserv@austin.ibm.com with a subject of

        IBM and AIX are registered trademarks of International Business
        Machines Corporation.
<H4>The NetBSD project</H4>
NetBSD is not vulnerable to the statd buffer overflow. It does not ship
with NFS locking programs (statd/lockd).
<H4>Red Hat Linux</H4>
Red Hat Linux is not vulnerable to the statd buffer overflow.  No versions
of Red Hat Linux include statd in any form.
<H4>Sun Microsystems</H4>
The statd vulnerability has been fixed by the following patches:

        SunOS version   Patch Id
        -------------   --------

        5.5.1           104166-03
        5.5.1_x86       104167-02
        5.5             103468-03
        5.5_x86         103469-03
        5.4             102769-04
        5.4_x86         102770-04
        4.1.4           102516-06
        4.1.3_U1        101592-09

SunOS 5.6 and 5.6_x86 are not vulnerable to this problem.

The vulnerability described in this advisory is not the same as that
described in Sun Security Bulletin #135.

Sun recommended and security patches (including checksums) are available from:

        <A HREF="http://sunsolve.sun.com/sunsolve/pubpatches/patches.html">http://sunsolve.sun.com/sunsolve/pubpatches/patches.html</A>

AUSCERT maintains a local mirror of Sun recommended and security
patches at:

        <A HREF="ftp://ftp.auscert.org.au/pub/mirrors/sunsolve1.sun.com/">ftp://ftp.auscert.org.au/pub/mirrors/sunsolve1.sun.com/</A>


<P>AUSCERT thanks Peter Marelas (The Fulcrum Consulting Group), Tim MacKenzie
(The Fulcrum Consulting Group) and CERT/CC for their assistance in the
preparation of this advisory.



<H3>Vendor Information</H3>

<P>Below is information we have received from vendors. If you do not see your
vendor's name below, contact the vendor directly for information.

<H3>NetBSD </H3>

NetBSD 1.2.1 and prior do not ship with rpc.statd.  NetBSD 1.3 ships an
rpc.statd that is not vulnerable.

<H3>Silicon Graphics Inc.</H3>

<P>Silicon Graphics Inc. has investigated the issue and has
recommended steps for neutralizing the exposure.  It is HIGHLY
RECOMMENDED that these measures be implemented on ALL SGI systems.

<P>For further information, please refer to Silicon Graphics
Inc. Security Advisory Number: 19971201-01-P1391 "Buffer Overrun
Vulnerability in statd(1M) Program"

<P>The SGI anonymous FTP site is sgigate.sgi.com ( or its
mirror, ftp.sgi.com.  Security information and patches can be found in
the ~ftp/security and ~ftp/patches directories, respectfully.

<!--#include virtual="/include/footer_nocopyright.html" -->
<P>Copyright 1997 Carnegie Mellon University.</P>


Revision History
Mar. 08, 1999   Updated patch information for Sun Microsystems.

Jul. 07, 1998   Updated information for Digital Equipment Corporation.

Feb. 12, 1998   Updated information for Hewlett-Packard and Data General Corporation.

Dec. 19, 1997   Vendor information for SGI added to the UPDATES section. 

Dec. 15, 1997   Vendor information for NetBSD has been added to the UPDATES section.