-----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 . 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-----