FreeBSD Security Advisory FreeBSD-SA-12:07.hostapd

Fabricante: FreeBSD
Fecha: 23/11/2012
Identificador: FreeBSD-SA-12:07.hostapd
FreeBSD Security Advisory FreeBSD-SA-12:07.hostapd
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ============================================================================= FreeBSD-SA-12:07.hostapd Security Advisory The FreeBSD Project Topic: Insufficient message length validation for EAP-TLS messages Category: contrib Module: wpa Announced: 2012-11-22 Credits: Timo Warns, Jouni Malinen Affects: FreeBSD 8.0 and later. Corrected: 2012-11-22 22:52:15 UTC (RELENG_8, 8.3-STABLE) 2012-11-22 22:52:15 UTC (RELENG_8_3, 8.3-RELEASE-p5) 2012-11-22 22:52:15 UTC (RELENG_9, 9.1-PRERELEASE) 2012-11-22 22:52:15 UTC (RELENG_9_0, 9.0-RELEASE-p5) 2012-11-22 22:52:15 UTC (RELENG_9_1, 9.1-RC1-p1) 2012-11-22 22:52:15 UTC (RELENG_9_1, 9.1-RC2-p1) 2012-11-22 22:52:15 UTC (RELENG_9_1, 9.1-RC3-p1) CVE Name: CVE-2012-4445 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit . I. Background The hostapd utility is an authenticator for IEEE 802.11 networks. It provides full support for WPA/IEEE 802.11i and can also act as an IEEE 802.1X Authenticator with a suitable backend Authentication Server (typically FreeRADIUS). EAP-TLS is the original, standard wireless LAN EAP authentication protocol defined in RFC 5216. It uses PKI to secure communication to a RADIUS authentication server or another type of authentication server. II. Problem Description The internal authentication server of hostapd does not sufficiently validate the message length field of EAP-TLS messages. III. Impact A remote attacker could cause the hostapd daemon to abort by sending specially crafted EAP-TLS messages, resulting in a Denial of Service. IV. Workaround No workaround is available, but systems not running hostapd are not vulnerable. Note that for FreeBSD 8.x systems, the EAP-TLS authentication method is not enabled by default. Systems running FreeBSD 8.x are only affected when hostapd is built with -DEAP_SERVER and as such, binary installations from the official release are not affected. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to 8-STABLE or 9-STABLE, or to the RELENG_8_3, or RELENG_9_0 security branch 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 FreeBSD 8.3 and 9.0 systems. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. [FreeBSD 8.x] # fetch http://security.FreeBSD.org/patches/SA-12:07/hostapd-8.patch # fetch http://security.FreeBSD.org/patches/SA-12:07/hostapd-8.patch.asc [FreeBSD 9.x] # fetch http://security.FreeBSD.org/patches/SA-12:07/hostapd.patch # fetch http://security.FreeBSD.org/patches/SA-12:07/hostapd.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 . 3) To update your vulnerable system via a binary patch: Systems running 8.3-RELEASE, 9.0-RELEASE, 9.1-RC1, 9.1-RC2, or 9.1-RC3 on the i386 or amd64 platforms can be updated via the freebsd-update(8) utility: # freebsd-update fetch # freebsd-update install VI. Correction details The following list contains the revision numbers of each file that was corrected in FreeBSD. Subversion: Branch/path Revision - ------------------------------------------------------------------------- stable/8/ r releng/8.3/ r stable/9/ r releng/9.0/ r releng/9.1/ r - ------------------------------------------------------------------------- VII. References http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-4445 The latest revision of this advisory is available at http://security.FreeBSD.org/advisories/FreeBSD-SA-12:07.hostapd.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 iEYEARECAAYFAlCuu28ACgkQFdaIBMps37JpRwCfVJmZsx+mAF22hqtL3YvcGU2x g9IAoIUfP/8eJjQACi30QVdvjFtGDw7f =SJZf -----END PGP SIGNATURE-----