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Gentoo Linux Security Advisory GLSA 200901-03 |
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http://security.gentoo.org/ |
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Severity: Normal |
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Title: pdnsd: Denial of Service and cache poisoning |
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Date: January 11, 2009 |
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Bugs: #231285 |
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ID: 200901-03 |
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Synopsis |
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======== |
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|
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Two errors in pdnsd allow for Denial of Service and cache poisoning. |
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|
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Background |
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========== |
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|
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pdnsd is a proxy DNS server with permanent caching that is designed to |
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cope with unreachable DNS servers. |
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|
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Affected packages |
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================= |
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|
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------------------------------------------------------------------- |
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Package / Vulnerable / Unaffected |
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------------------------------------------------------------------- |
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1 net-dns/pdnsd < 1.2.7 >= 1.2.7 |
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|
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Description |
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=========== |
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|
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Two issues have been reported in pdnsd: |
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|
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* The p_exec_query() function in src/dns_query.c does not properly |
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handle many entries in the answer section of a DNS reply, related to |
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a "dangling pointer bug" (CVE-2008-4194). |
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|
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* The default value for query_port_start was set to 0, disabling UDP |
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source port randomization for outgoing queries (CVE-2008-1447). |
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|
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Impact |
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====== |
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|
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An attacker could exploit the second weakness to poison the cache of |
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pdnsd and thus spoof DNS traffic, which could e.g. lead to the |
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redirection of web or mail traffic to malicious sites. The first issue |
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can be exploited by enticing pdnsd to send a query to a malicious DNS |
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server, or using the port randomization weakness, and might lead to a |
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Denial of Service. |
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|
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Workaround |
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========== |
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|
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Port randomization can be enabled by setting the "query_port_start" |
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option to 1024 which would resolve the CVE-2008-1447 issue. |
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Resolution |
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========== |
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All pdnsd users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=net-dns/pdnsd-1.2.7" |
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|
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References |
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========== |
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|
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[ 1 ] CVE-2008-1447 |
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http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-1447 |
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[ 2 ] CVE-2008-4194 |
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http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-4194 |
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|
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Availability |
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============ |
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This GLSA and any updates to it are available for viewing at |
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the Gentoo Security Website: |
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http://security.gentoo.org/glsa/glsa-200901-03.xml |
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|
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Concerns? |
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========= |
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Security is a primary focus of Gentoo Linux and ensuring the |
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confidentiality and security of our users machines is of utmost |
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importance to us. Any security concerns should be addressed to |
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security@g.o or alternatively, you may file a bug at |
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http://bugs.gentoo.org. |
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|
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License |
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======= |
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Copyright 2009 Gentoo Foundation, Inc; referenced text |
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belongs to its owner(s). |
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|
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The contents of this document are licensed under the |
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Creative Commons - Attribution / Share Alike license. |
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|
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http://creativecommons.org/licenses/by-sa/2.5 |
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