The Internet Key Exchange version 1 (IKEv1) implementation (isakmp_agg.c) in racoon in ipsec-tools before 0.6.3, when running in aggressive mode, allows remote attackers to cause a denial of service (null dereference and crash) via crafted IKE packets, as demonstrated by the PROTOS ISAKMP Test Suite for IKEv1.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9857
http://www.vupen.com/english/advisories/2005/2521
http://www.securityfocus.com/bid/15523
http://www.securityfocus.com/archive/1/436343/100/0/threaded
http://www.novell.com/linux/security/advisories/2005_70_ipsec.html
http://www.niscc.gov.uk/niscc/docs/re-20051114-01014.pdf?lang=en
http://www.mandriva.com/security/advisories?name=MDKSA-2006:020
http://www.gentoo.org/security/en/glsa/glsa-200512-04.xml
http://www.ee.oulu.fi/research/ouspg/protos/testing/c09/isakmp/
http://www.debian.org/security/2006/dsa-965
http://sourceforge.net/mailarchive/forum.php?thread_id=9017454&forum_id=32000
http://securitytracker.com/id?1015254
http://secunia.com/advisories/20210
http://secunia.com/advisories/19833
http://secunia.com/advisories/18742
http://secunia.com/advisories/18616
http://secunia.com/advisories/18115
http://secunia.com/advisories/17980
http://secunia.com/advisories/17822
http://secunia.com/advisories/17668
http://rhn.redhat.com/errata/RHSA-2006-0267.html
http://archives.neohapsis.com/archives/bugtraq/2005-12/0161.html