From koon@gentoo.org Sat Sep 17 08:34:05 2005 From: Thierry Carrez To: gentoo-announce@lists.gentoo.org Cc: full-disclosure@lists.grok.org.uk, bugtraq@securityfocus.com, security-alerts@linuxsecurity.com Date: Sat, 17 Sep 2005 14:31:52 +0200 Subject: [Full-disclosure] ERRATA: [ GLSA 200507-20 ] Shorewall: Security policy bypass - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Gentoo Linux Security Advisory [ERRATA UPDATE] GLSA 200507-20:02 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - http://security.gentoo.org/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Severity: Low Title: Shorewall: Security policy bypass Date: July 22, 2005 Updated: September 14, 2005 Bugs: #99398 ID: 200507-20:02 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Errata ====== The "unaffected" version was incorrectly set to 2.4.1 in the initial advisory, the correct "unaffected" version is 2.4.2. The corrected sections appear below. Synopsis ======== A vulnerability in Shorewall allows clients authenticated by MAC address filtering to bypass all other security rules. Background ========== Shorewall is a high level tool for configuring Netfilter, the firewall facility included in the Linux Kernel. Affected packages ================= ------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 net-firewall/shorewall <= 2.4.1 >= 2.4.2 Description =========== Shorewall fails to enforce security policies if configured with "MACLIST_DISPOSITION" set to "ACCEPT" or "MACLIST_TTL" set to a value greater or equal to 0. Impact ====== A client authenticated by MAC address filtering could bypass all security policies, possibly allowing him to gain access to restricted services. The default installation has MACLIST_DISPOSITION=REJECT and MACLIST_TTL=(blank) (equivalent to 0). This can be checked by looking at the settings in /etc/shorewall/shorewall.conf Workaround ========== Set "MACLIST_TTL" to "0" and "MACLIST_DISPOSITION" to "REJECT" in the Shorewall configuration file (usually /etc/shorewall/shorewall.conf). Resolution ========== All Shorewall users should upgrade to the latest available version: # emerge --sync # emerge --ask --oneshot --verbose net-firewall/shorewall References ========== [ 1 ] CAN-2005-2317 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-2317 [ 2 ] Shorewall Announcement http://www.shorewall.net/News.htm#20050717 Availability ============ This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200507-20.xml Concerns? ========= Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at http://bugs.gentoo.org. License ======= Copyright 2005 Gentoo Foundation, Inc; referenced text belongs to its owner(s). The contents of this document are licensed under the Creative Commons - Attribution / Share Alike license. http://creativecommons.org/licenses/by-sa/2.0 [ Part 1.2, "OpenPGP digital signature" Application/PGP-SIGNATURE ] [ 264bytes. ] [ Unable to print this part. ] [ Part 2: "Attached Text" ] _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/