FreeBSD Security Advisories
2013-Feb-19 14:04 UTC
FreeBSD Security Advisory FreeBSD-SA-13:02.libc
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ============================================================================FreeBSD-SA-13:02.libc Security Advisory The FreeBSD Project Topic: glob(3) related resource exhaustion Category: core Module: libc Announced: 2013-02-19 Affects: All supported versions of FreeBSD. Corrected: 2013-02-05 09:53:32 UTC (stable/7, 7.4-STABLE) 2013-02-19 13:27:20 UTC (releng/7.4, 7.4-RELEASE-p12) 2013-02-05 09:53:32 UTC (stable/8, 8.3-STABLE) 2013-02-19 13:27:20 UTC (releng/8.3, 8.3-RELEASE-p6) 2013-02-05 09:53:32 UTC (stable/9, 9.1-STABLE) 2013-02-19 13:27:20 UTC (releng/9.0, 9.0-RELEASE-p6) 2013-02-19 13:27:20 UTC (releng/9.1, 9.1-RELEASE-p1) CVE Name: CVE-2010-2632 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 glob(3) function is a pathname generator that implements the rules for file name pattern matching used by the shell. II. Problem Description GLOB_LIMIT is supposed to limit the number of paths to prevent against memory or CPU attacks. The implementation however is insufficient. III. Impact An attacker that is able to exploit this vulnerability could cause excessive memory or CPU usage, resulting in a Denial of Service. A common target for a remote attacker could be ftpd(8). IV. Workaround No workaround is available. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to a supported FreeBSD stable or release / security branch (releng) dated after the correction date. 2) To update your vulnerable system via a source code patch: The following patches have been verified to apply to the applicable FreeBSD release branches. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. # fetch http://security.FreeBSD.org/patches/SA-13:02/libc.patch # fetch http://security.FreeBSD.org/patches/SA-13:02/libc.patch.asc # gpg --verify libc.patch.asc b) Execute the following commands as root: # cd /usr/src # patch < /path/to/patch Recompile the operating system using buildworld and installworld as described in <URL:http://www.FreeBSD.org/handbook/makeworld.html>. Restart all daemons, or reboot the system. 3) To update your vulnerable system via a binary patch: Systems running a RELEASE version of FreeBSD on the i386 or amd64 platforms can be updated via the freebsd-update(8) utility: # freebsd-update fetch # freebsd-update install Restart all daemons, or reboot the system. VI. Correction details The following list contains the revision numbers of each file that was corrected in FreeBSD. Branch/path Revision - ------------------------------------------------------------------------- stable/7/ r246357 releng/7.4/ r246989 stable/8/ r246357 releng/8.3/ r246989 stable/9/ r246357 releng/9.0/ r246989 releng/9.1/ r246989 - ------------------------------------------------------------------------- VII. References http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-2632 The latest revision of this advisory is available at http://security.FreeBSD.org/advisories/FreeBSD-SA-13:02.libc.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (FreeBSD) iEYEARECAAYFAlEjf80ACgkQFdaIBMps37JFUgCfUrw8Ky4U19COja6fna49Calv z/YAn1JSGxzHCo8vLj4XhtXqrQt68or4 =mCPv -----END PGP SIGNATURE-----