news 28 Posted January 14, 2010 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Gentoo Linux Security Advisory GLSA 201001-05 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - http://security.gentoo.org/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Severity: Normal Title: net-snmp: Authorization bypass Date: January 13, 2010 Bugs: #250429 ID: 201001-05 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Synopsis ======== A remote attacker can bypass the tcp-wrappers client authorization in net-snmp. Background ========== net-snmp bundles software for generating and retrieving SNMP data. Affected packages ================= ------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 net-analyzer/net-snmp < 5.4.2.1-r1 >= 5.4.2.1-r1 Description =========== The netsnmp_udp_fmtaddr() function (snmplib/snmpUDPDomain.c), when using TCP wrappers for client authorization, does not properly parse hosts.allow rules. Impact ====== A remote, unauthenticated attacker could bypass the ACL filtering, possibly resulting in the execution of arbitrary SNMP queries. Workaround ========== If possible, protect net-snmp with custom iptables rules: iptables -s [client] -d [host] -p udp --dport 161 -j ACCEPT iptables -s 0.0.0.0/0 -d [host] -p udp --dport 161 -j DROP Resolution ========== All net-snmp users should upgrade to the latest version: # emerge --sync # emerge --ask --oneshot --verbose ">=net-analyzer/net-snmp-5.4.2.1-r1" References ========== [ 1 ] CVE-2008-6123 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-6123 Availability ============ This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-201001-05.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 ( -at -) gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org. License ======= Copyright 2010 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/2.5 Share this post Link to post