Date: 12 January 2006
References: ESB-2006.0867
Click here for printable version
Click here for PGP verifiable version
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2006.0034 -- [UNIX/Linux][FreeBSD]
Texindex temporary file privilege escalation
12 January 2006
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: texindex
Publisher: FreeBSD
Operating System: FreeBSD
UNIX variants (UNIX, Linux, OSX)
Impact: Overwrite Arbitrary Files
Access: Existing Account
CVE Names: CVE-2005-3011
Original Bulletin:
ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-06:01.texindex.asc
- --------------------------BEGIN INCLUDED TEXT--------------------
- -----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
=============================================================================
FreeBSD-SA-06:01.texindex Security Advisory
The FreeBSD Project
Topic: Texindex temporary file privilege escalation
Category: contrib
Module: texinfo
Announced: 2006-01-11
Credits: Frank Lichtenheld
Affects: All FreeBSD releases.
Corrected: 2006-01-11 08:02:16 UTC (RELENG_6, 6.0-STABLE)
2006-01-11 08:03:18 UTC (RELENG_6_0, 6.0-RELEASE-p2)
2006-01-11 08:03:55 UTC (RELENG_5, 5.4-STABLE)
2006-01-11 08:04:33 UTC (RELENG_5_4, 5.4-RELEASE-p9)
2006-01-11 08:05:54 UTC (RELENG_5_3, 5.3-RELEASE-p24)
2006-01-11 08:06:47 UTC (RELENG_4, 4.11-STABLE)
2006-01-11 08:07:18 UTC (RELENG_4_11, 4.11-RELEASE-p14)
2006-01-11 08:08:08 UTC (RELENG_4_10, 4.10-RELEASE-p20)
CVE Name: CAN-2005-3011
For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit
<URL:http://www.freebsd.org/security/>.
0. Revision History.
v1.0 2006-01-11 Initial release.
v1.1 2006-01-11 Corrected instructions for rebuilding texindex.
I. Background
TeX is a document typesetting system which is popular in the mathematics,
physics, and computer science realms because of its ability to typeset
complex mathematical formulas. texindex(1) is a utility which is often
used to generate a sorted index of a TeX file.
II. Problem Description
The "sort_offline" function used by texindex(1) employs the "maketempname"
function, which produces predictable file names and fails to validate that
the paths do not exist.
III. Impact
These predictable temporary file names are problematic because they
allow an attacker to take advantage of a race condition in order to
execute a symlink attack, which could enable them to overwrite files
on the system in the context of the user running the texindex(1) utility.
IV. Workaround
No workaround is available, but the problematic code is only executed
if the input file being processed is 500kB or more in length; as a
result, users working with documents of less than several hundred pages
are very unlikely to be affected.
V. Solution
Perform one of the following:
1) Upgrade your vulnerable system to 4-STABLE, 5-STABLE, or 6-STABLE,
or to the RELENG_6_0, RELENG_5_4, RELENG_5_3, RELENG_4_11, or
RELENG_4_10 security branch dated after the correction date.
2) To patch your present system:
The following patches have been verified to apply to FreeBSD 4.10,
4.11, 5.3, 5.4, and 6.0 systems.
a) Download the relevant patch from the location below, and verify the
detached PGP signature using your PGP utility.
[FreeBSD 4.x and 5.x]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:01/texindex5x.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:01/texindex5x.patch.asc
[FreeBSD 6.x]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:01/texindex.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-06:01/texindex.patch.asc
b) Execute the following commands as root:
# cd /usr/src
# patch < /path/to/patch
# cd /usr/src/gnu/usr.bin/texinfo/libtxi
# make obj && make depend && make
# cd /usr/src/gnu/usr.bin/texinfo/texindex
# make obj && make depend && make && make install
VI. Correction details
The following list contains the revision numbers of each file that was
corrected in FreeBSD.
Branch Revision
Path
- - -------------------------------------------------------------------------
RELENG_4
contrib/texinfo/util/texindex.c 1.1.1.3.2.4
RELENG_4_11
src/UPDATING 1.73.2.91.2.15
src/sys/conf/newvers.sh 1.44.2.39.2.18
contrib/texinfo/util/texindex.c 1.1.1.3.2.3.6.1
RELENG_4_10
src/UPDATING 1.73.2.90.2.21
src/sys/conf/newvers.sh 1.44.2.34.2.22
contrib/texinfo/util/texindex.c 1.1.1.3.2.3.4.1
RELENG_5
contrib/texinfo/util/texindex.c 1.1.1.7.4.1
RELENG_5_4
src/UPDATING 1.342.2.24.2.18
src/sys/conf/newvers.sh 1.62.2.18.2.14
contrib/texinfo/util/texindex.c 1.1.1.7.8.1
RELENG_5_3
src/UPDATING 1.342.2.13.2.27
src/sys/conf/newvers.sh 1.62.2.15.2.29
contrib/texinfo/util/texindex.c 1.1.1.7.6.1
RELENG_6
contrib/texinfo/util/texindex.c 1.1.1.8.2.1
RELENG_6_0
src/UPDATING 1.416.2.3.2.7
src/sys/conf/newvers.sh 1.69.2.8.2.3
contrib/texinfo/util/texindex.c 1.1.1.8.4.1
- - -------------------------------------------------------------------------
VII. References
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-3011
The latest revision of this advisory is available at
ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-06:01.texindex.asc
- -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (FreeBSD)
iD8DBQFDxNZZFdaIBMps37IRAkQ5AKCayEHnnoglWAyY2wA22huF9xmIxgCdFwpn
ePrdykp4BUjKqAMYCUupMK8=
=q74p
- -----END PGP SIGNATURE-----
- --------------------------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.
NOTE: Third Party Rights
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 follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
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 author's website 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/render.html?cid=1980
If you believe that your computer system has been compromised or attacked in
any way, we encourage you to let us know by completing the secure National IT
Incident Reporting Form at:
http://www.auscert.org.au/render.html?it=3192
===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072
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 member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967
iQCVAwUBQ8Wv4Sh9+71yA2DNAQJJJAP/VsSelHzD8VCo+bIIhQNpwR/qCyr5RhcA
VM++3ELMuO8dUkfQ7GAcnxklUyJHT9K3uRGgmZlAdeIRbGiVI9kbvSnFkcTAcVUC
JDYmvnrdPdBikTHg9q1JT8fc39FsYc9xgF3S9duVD5OktgacNZJZJcnwQRC4euZ+
cke2hExxwK8=
=/FAn
-----END PGP SIGNATURE-----
|