-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ============================================================================= FreeBSD-SA-04:07.cvs Security Advisory The FreeBSD Project Topic: CVS path validation errors Category: contrib Module: contrib_cvs Announced: 2004-04-15 Revised: 2004-04-16 Credits: Sebastian Krahmer Derek Robert Price Affects: All FreeBSD versions prior to 4.10-RELEASE Corrected: 2004-04-15 15:35:26 UTC (RELENG_4, 4.10-BETA) 2004-04-15 15:42:50 UTC (RELENG_5_2, 5.2.1-RELEASE-p5) 2004-04-15 15:59:05 UTC (RELENG_4_9, 4.9-RELEASE-p5) 2004-04-15 15:59:54 UTC (RELENG_4_8, 4.8-RELEASE-p18) CVE Name: CAN-2004-0180, CAN-2004-0405 FreeBSD only: NO 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 2004-04-14 Initial release. v1.1 2004-04-15 Added additional CVE name. Corrected affected release names. Reworded `Workaround' section. I. Background The Concurrent Versions System (CVS) is a version control system. It may be used to access a repository locally, or to access a `remote repository' using a number of different methods. When accessing a remote repository, the target machine runs the CVS server to fulfill client requests. II. Problem Description Two programming errors were discovered in which path names handled by CVS were not properly validated. In one case, CAN-2004-0180, the CVS client accepts absolute path names from the server when determining which files to update. In another case, CAN-2004-0405, the CVS server accepts relative path names from the client when determining which files to transmit, including those containing references to parent directories (`../'). III. Impact These programming errors generally only have a security impact when dealing with remote CVS repositories. A malicious CVS server may cause a CVS client to overwrite arbitrary files on the client's system. A CVS client may request RCS files from a remote system other than those in the repository specified by $CVSROOT. These RCS files need not be part of any CVS repository themselves. IV. Workaround Users of CVS clients should avoid accessing remote repositories. Administrators of CVS repositories should disable remote access. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to 4-STABLE; or to the RELENG_5_2, RELENG_4_9, or RELENG_4_8 security branch dated after the correction date. 2) To patch your present system: The following patches have been verified to apply to FreeBSD 4.8, 4.9, 5.1, and 5.2 systems. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-04:07/cvs.patch # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-04:07/cvs.patch.asc b) Execute the following commands as root: # cd /usr/src # patch < /path/to/patch # cd /usr/src/gnu/usr.bin/cvs # 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 src/contrib/cvs/src/client.c 1.2.2.7 src/contrib/cvs/src/modules.c 1.1.1.5.2.4 RELENG_5_2 src/UPDATING 1.282.2.13 src/sys/conf/newvers.sh 1.56.2.12 src/contrib/cvs/src/client.c 1.10.4.1 src/contrib/cvs/src/modules.c 1.1.1.8.6.2 RELENG_4_9 src/UPDATING 1.73.2.89.2.6 src/sys/conf/newvers.sh 1.44.2.32.2.6 src/contrib/cvs/src/client.c 1.2.2.6.4.1 src/contrib/cvs/src/modules.c 1.1.1.5.2.3.4.1 RELENG_4_8 src/UPDATING 1.73.2.80.2.21 src/sys/conf/newvers.sh 1.44.2.29.2.19 src/contrib/cvs/src/client.c 1.2.2.6.2.1 src/contrib/cvs/src/modules.c 1.1.1.5.2.3.2.1 - ------------------------------------------------------------------------- VII. References http://ccvs.cvshome.org/servlets/NewsItemView?newsID=102 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (FreeBSD) iD8DBQFAf9JjFdaIBMps37IRAvX1AKCLBj7AKXeH0H+MQdQPOOlQESzi+wCZAV0I NMgLCxOS/j9H34OJlYOLflU= =W0D4 -----END PGP SIGNATURE-----