|
Home : Advisories : Buffer Overrun Vulnerability in statd(1M) Program
Title: |
Buffer Overrun Vulnerability in statd(1M) Program |
Released by: |
CERT |
Date: |
5th December 1997 |
Printable version: |
Click here |
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
CERT Advisory CA-97.26.statd
Original issue date: Dec. 5, 1997
Last revised: March 08, 1999 - Updated patch information for Sun
Microsystems
A complete revision history is at the end of this file.
_________________________________________________________________
Buffer Overrun Vulnerability in statd(1M) Program
_________________________________________________________________
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.
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.
This vulnerability may allow local users, as well as remote users to
gain root privileges.
Exploit information involving this vulnerability has been made
publicly available.
This vulnerability is different to the statd vulnerability described
in CERT/CC advisory CA-96.09.
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.
This advisory will be updated as more information becomes available.
_________________________________________________________________
I. Description
AUSCERT has received information concerning a vulnerability in some
vendor versions of the RPC server, statd(1M).
statd provides network status monitoring. It interacts with lockd to
provide crash and recovery functions for the locking services on NFS.
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.
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.
Sites can check whether they are running statd by:
On system V like systems:
# ps -fe |grep statd
root 973 1 0 14:41:46 ? 0:00 /usr/lib/nfs/statd
On BSD like systems:
# 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.
II. Impact
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.
III. Workarounds/Solution
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).
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 3.2).
3.1 Vendor information
The following vendors have provided information concerning the
vulnerability in statd.
BSDI
Data General Corporation
Digital Equipment Corporation
Hewlett-Packard
IBM Corporation
The NetBSD Project
Red Hat Software
Sun Microsystems
Specific vendor information has been placed in Appendix A.
If the statd program is required at your site and your vendor is not
listed, you should contact your vendor directly.
If you do not require the statd program then it should be disabled
(Section 3.2).
3.2 Disabling statd
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).
_________________________________________________________________
Appendix A Vendor information
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.
BSDI
No versions of BSD/OS are vulnerable to this problem.
Data General Corporation
This problem is under investigation.
Digital Equipment Corporation
A DIGITAL EQUIPMENT CORPORATION ADVISORY, SSRT0456U, concerning
"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:
http://www.service.digital.com/html/patch_service.html
Use the FTP access option, select DIGITAL_UNIX directory
then choose the appropriate version directory
and download the patch accordingly.
Hewlett-Packard
HP is not vulnerable.
IBM Corporation
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
command:
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
command:
instfix -ik IX55931
Or run the following command:
lslpp -h bos.net.nfs.client
Your version of bos.net.nfs.client should be 4.1.4.7 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:
http://service.software.ibm.com/aixsupport/
or send e-mail to aixserv@austin.ibm.com with a subject of
"FixDist".
IBM and AIX are registered trademarks of International Business
Machines Corporation.
The NetBSD project
NetBSD is not vulnerable to the statd buffer overflow. It does not ship
with NFS locking programs (statd/lockd).
Red Hat Linux
Red Hat Linux is not vulnerable to the statd buffer overflow. No versions
of Red Hat Linux include statd in any form.
Sun Microsystems
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:
http://sunsolve.sun.com/sunsolve/pubpatches/patches.html
AUSCERT maintains a local mirror of Sun recommended and security
patches at:
http://ftp.auscert.org.au/pub/mirrors/sunsolve1.sun.com/
_________________________________________________________________
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.
______________________________________________________________________
UPDATES
Vendor Information
Below is information we have received from vendors. If you do not see
your vendor's name below, contact the vendor directly for information.
NetBSD
NetBSD 1.2.1 and prior do not ship with rpc.statd. NetBSD 1.3 ships an
rpc.statd that is not vulnerable.
Silicon Graphics Inc.
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.
For further information, please refer to Silicon Graphics Inc.
Security Advisory Number: 19971201-01-P1391 "Buffer Overrun
Vulnerability in statd(1M) Program"
The SGI anonymous FTP site is sgigate.sgi.com (204.94.209.1) or its
mirror, ftp.sgi.com. Security information and patches can be found in
the ~ftp/security and ~ftp/patches directories, respectfully.
______________________________________________________________________
This document is available from:
http://www.cert.org/advisories/CA-97.26.statd.html.
______________________________________________________________________
CERT/CC Contact Information
Email: cert@cert.org
Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
Postal address:
CERT Coordination Center
Software Engineering Institute
Carnegie Mellon University
Pittsburgh PA 15213-3890
U.S.A.
CERT personnel answer the hotline 08:00-20:00 EST(GMT-5) / EDT(GMT-4)
Monday through Friday; they are on call for emergencies during other
hours, on U.S. holidays, and on weekends.
Using encryption
We strongly urge you to encrypt sensitive information sent by email.
Our public PGP key is available from http://www.cert.org/CERT_PGP.key.
If you prefer to use DES, please call the CERT hotline for more
information.
Getting security information
CERT publications and other security information are available from
our web site http://www.cert.org/.
To be added to our mailing list for advisories and bulletins, send
email to cert-advisory-request@cert.org and include SUBSCRIBE
your-email-address in the subject of your message.
Copyright 1999 Carnegie Mellon University.
Conditions for use, disclaimers, and sponsorship information can be
found in http://www.cert.org/legal_stuff.html.
* "CERT" and "CERT Coordination Center" are registered in the U.S.
Patent and Trademark Office
______________________________________________________________________
NO WARRANTY
Any material furnished by Carnegie Mellon University and the Software
Engineering Institute is furnished on an "as is" basis. Carnegie
Mellon University makes no warranties of any kind, either expressed or
implied as to any matter including, but not limited to, warranty of
fitness for a particular purpose or merchantability, exclusivity or
results obtained from use of the material. Carnegie Mellon University
does not make any warranty of any kind with respect to freedom from
patent, trademark, or copyright infringement.
______________________________________________________________________
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 Corpor
ation.
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 sec
tion.
-----BEGIN PGP SIGNATURE-----
Version: PGP for Personal Privacy 5.0
Charset: noconv
iQA/AwUBOBTARVr9kb5qlZHQEQJfCQCeIKB1FQzkfz8j4nZR7lIP3uz/X/gAn3Pw
x0Njw0N1p3jv99b1sRLZPS7b
=16aY
-----END PGP SIGNATURE-----
|