FreeBSD Security Advisories
2007-May-23 16:20 UTC
FreeBSD Security Advisory FreeBSD-SA-07:04.file
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ============================================================================FreeBSD-SA-07:04.file Security Advisory The FreeBSD Project Topic: Heap overflow in file(1) Category: contrib Module: file Announced: 2007-05-23 Affects: All FreeBSD releases. Corrected: 2007-05-23 16:12:51 UTC (RELENG_6, 6.2-STABLE) 2007-05-23 16:13:07 UTC (RELENG_6_2, 6.2-RELEASE-p5) 2007-05-23 16:13:20 UTC (RELENG_6_1, 6.1-RELEASE-p17) 2007-05-23 16:12:10 UTC (RELENG_5, 5.5-STABLE) 2007-05-23 16:12:35 UTC (RELENG_5_5, 5.5-RELEASE-p13) CVE Name: CVE-2007-1536 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit <URL:http://security.FreeBSD.org/>. I. Background The file(1) utility attempts to classify file system objects based on filesystem, magic number and language tests. The libmagic(3) library provides most of the functionality of file(1) and may be used by other applications. II. Problem Description When writing data into a buffer in the file_printf function, the length of the unused portion of the buffer is not correctly tracked, resulting in a buffer overflow when processing certain files. III. Impact An attacker who can cause file(1) to be run on a maliciously constructed input can cause file(1) to crash. It may be possible for such an attacker to execute arbitrary code with the privileges of the user running file(1). The above also applies to any other applications using the libmagic(3) library. IV. Workaround No workaround is available, but systems where file(1) and other libmagic(3)-using applications are never run on untrusted input are not vulnerable. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to 5-STABLE, or 6-STABLE, or to the RELENG_6_2, RELENG_6_1, or RELENG_5_5 security branch dated after the correction date. 2) To patch your present system: The following patches have been verified to apply to FreeBSD 5.5, 6.1, and 6.2 systems. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. [FreeBSD 5.5] # fetch http://security.FreeBSD.org/patches/SA-07:04/file5.patch # fetch http://security.FreeBSD.org/patches/SA-07:04/file5.patch.asc [FreeBSD 6.1 and 6.2] # fetch http://security.FreeBSD.org/patches/SA-07:04/file6.patch # fetch http://security.FreeBSD.org/patches/SA-07:04/file6.patch.asc b) Execute the following commands as root: # cd /usr/src # patch < /path/to/patch # cd /usr/src/lib/libmagic # 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_5 src/contrib/file/file.h 1.1.1.7.2.1 src/contrib/file/funcs.c 1.1.1.1.2.1 src/contrib/file/magic.c 1.1.1.1.2.1 RELENG_5_5 src/UPDATING 1.342.2.35.2.13 src/sys/conf/newvers.sh 1.62.2.21.2.15 src/contrib/file/file.h 1.1.1.7.8.1 src/contrib/file/funcs.c 1.1.1.1.8.1 src/contrib/file/magic.c 1.1.1.1.8.1 RELENG_6 src/contrib/file/file.h 1.1.1.8.2.1 src/contrib/file/funcs.c 1.1.1.2.2.1 src/contrib/file/magic.c 1.1.1.2.2.1 RELENG_6_2 src/UPDATING 1.416.2.29.2.8 src/sys/conf/newvers.sh 1.69.2.13.2.8 src/contrib/file/file.h 1.1.1.8.8.1 src/contrib/file/funcs.c 1.1.1.2.8.1 src/contrib/file/magic.c 1.1.1.2.8.1 RELENG_6_1 src/UPDATING 1.416.2.22.2.19 src/sys/conf/newvers.sh 1.69.2.11.2.19 src/contrib/file/file.h 1.1.1.8.6.1 src/contrib/file/funcs.c 1.1.1.2.6.1 src/contrib/file/magic.c 1.1.1.2.6.1 - ------------------------------------------------------------------------- VII. References http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-1536 The latest revision of this advisory is available at http://security.FreeBSD.org/advisories/FreeBSD-SA-07:04.file.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (FreeBSD) iD8DBQFGVGjhFdaIBMps37IRAgogAJ9o/0yCxtRi527rgvhg/BoC/AvEsQCfcwMX ABl7JIb1XiY6QKWQ6UfwlGA=meQ0 -----END PGP SIGNATURE-----