Operating System:

Published:

20 June 2001

Protect yourself against future threats.

-----BEGIN PGP SIGNED MESSAGE-----

===========================================================================
             AUSCERT External Security Bulletin Redistribution

                 ESB-2001.247 -- OpenBSD Security Advisory
               patch for exec+ptrace security hole available
                               21 June 2001

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

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:                execve(2)
Vendor:                 OpenBSD
Operating System:       OpenBSD
Impact:                 Increased Privileges
Access Required:        Existing Account

- --------------------------BEGIN INCLUDED TEXT--------------------

A race condition exists in the kernel execve(2) implementation that opens
a small window of vulnerability for a non-privileged user to
ptrace(2) attach to a suid/sgid process.

2.8 patch:
ftp://ftp.openbsd.org/pub/OpenBSD/patches/2.8/common/030_kernexec.patch

2.9 patch:
ftp://ftp.openbsd.org/pub/OpenBSD/patches/2.9/common/007_kernexec.patch

The fix has also been committed to the 2.8 and 2.9 stable branches.

The bug was found by Georgi Guninski; Art Grabowski came up with a fix.

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.

This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content.  The decision to use any or all of this information is
the responsibility of each user or organisation, and should be done so in
accordance with site policies and procedures.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the original authors to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

	http://www.auscert.org.au/Information/advisories.html

If you believe that your system has been compromised, contact AusCERT or
your representative in FIRST (Forum of Incident Response and Security
Teams).

Internet Email: auscert@auscert.org.au
Facsimile:	(07) 3365 7031
Telephone:	(07) 3365 4417 (International: +61 7 3365 4417)
		AusCERT personnel answer during Queensland business hours
		which are GMT+10:00 (AEST).
		On call after hours for emergencies.

-----BEGIN PGP SIGNATURE-----
Version: 2.6.3i
Charset: noconv
Comment: ftp://ftp.auscert.org.au/pub/auscert/AUSCERT_PGP.key

iQCVAwUBOzHoJSh9+71yA2DNAQHkvQP/cwrGo5AO+nJcZg/7zsQdQQvJ+F8yijyO
PLoPJP5lAn9CRtOnPsmTaz5gtK+23l9A33NCk9/8ZfGYmss0B0IJLXGfeZ6Ar+wU
buKl5nUA3YM0i5jKQKqBW7l7KQg1wCK7bM3F6su8vThmPElUtx1dbztIpN70FOTP
d3W/QmYLoAY=
=fOxz
-----END PGP SIGNATURE-----