-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 NetBSD Security Advisory 2006-003 ================================= Topic: Multiple denial of services issues with racoon Version: NetBSD-current: source prior to November 21, 2005 NetBSD 3.0: not affected NetBSD 2.1: affected NetBSD 2.0.*: affected NetBSD 2.0: affected NetBSD 1.6.*: affected NetBSD 1.6: affected pkgsrc: ipsec-tools packages prior to 0.6.3 Severity: Denial of service, in some cases anonymously Fixed: NetBSD-current: November 21, 2005 NetBSD-2-1 branch: January 19, 2006 (2.1.1 will include the fix) NetBSD-2-0 branch: January 19, 2006 (2.0.4 will include the fix) NetBSD-2 branch: January 19, 2006 pkgsrc: ipsec-tools-0.6.3 corrects this issue Abstract ======== The University of Oulu (Finland) released a test-suite for the Internet Security Association and Key Management Protocol (ISAKMP) daemons available in various devices and operating systems. During their testing they identified a number of issues in various implementations. On further testing the racoon daemon supplied with NetBSD and in pkgsrc were found to be vulnerable to a number of denial of service attacks. http://www.ee.oulu.fi/research/ouspg/protos/testing/c09/isakmp/index.html http://www.niscc.gov.uk/niscc/docs/re-20051114-01014.pdf Technical Details ================= NetBSD up to the 3.0 release used the racoon daemon from the KAME project. For the 3.0 release this was changed to the ipsec-tools racoon daemon. During the testing of both these ISAKMP implementations on NetBSD a number of denial of service issues were identified. There are three vulnerabilities that are a result of two code paths in the source which allow a malicious attacker to crash the racoon daemon. For this attack to be successful a number of factors must occur: - - The racoon daemon must be enabled (it is disabled by default) - - The racoon daemon must be configured for aggressive mode (not recommended) - - In order to trigger 2 of the 3 vulnerabilities the attacker must have an entry in the SPD In addition to this the PROTOS test suite had a number of configuration prerequisites including: - - racoon's configuration to be 3DES/SHA1/DH2 - - no lifetime proposal or obey mode None of the issues are currently know to result in the execution of arbitrary code. Solutions and Workarounds ========================= A limited workaround could be to use ip filtering to only allow ISAKMP traffic (500/udp, and 4500/udp if you use NAT-T) from known trusted sources. The following instructions describe how to upgrade your racoon binaries by updating your source tree and rebuilding and installing a new version of racoon. * NetBSD-current: Systems running NetBSD-current dated from before 2005-11-20 should be upgraded to NetBSD-current dated 2005-11-21 or later. The following directories need to be updated from the netbsd-current CVS branch (aka HEAD): crypto/dist/ipsec-tools lib/libipsec To update from CVS, re-build, and re-install racoon: # cd src # cvs update -d -P crypto/dist/ipsec-tools # cvs update -d -P lib/libipsec # cd lib/libipsec # make USETOOLS=no cleandir dependall # make USETOOLS=no install # cd ../../sbin/setkey # make USETOOLS=no cleandir dependall # make USETOOLS=no install # cd ../../usr.sbin/racoon # make USETOOLS=no cleandir dependall # make USETOOLS=no install * NetBSD 2.*: Systems running NetBSD 2.* sources dated from before 2006-01-18 should be upgraded from NetBSD 2.* sources dated 2006-01-19 or later. The following file needs to be updated from the netbsd-2, netbsd-2-0 or netbsd-2-1 CVS branch: crypto/dist/kame/racoon/isakmp_agg.c To update from CVS, re-build, and re-install racoon: # cd src # cvs update -d -P -r crypto/dist/kame/racoon/isakmp_agg.c # cd usr.sbin/racoon # make USETOOLS=no cleandir dependall # make USETOOLS=no install Thanks To ========= The University of Oulu (Finland) for making the PROTOS test suite publicly available. Ipsec-tools core team member Yvan Vanhullebus for responding quickly to the identified issues and helping to provide fixes. Adrian Portelli for performing the PROTOS testing, documenting and reporting the issues. Dave Huang for reporting a racoon crash to NetBSD. Revision History ================ 2006-03-29 Initial release More Information ================ Advisories may be updated as new information becomes available. The most recent version of this advisory (PGP signed) can be found at ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2006-003.txt.asc Information about NetBSD and NetBSD security can be found at http://www.NetBSD.org/ and http://www.NetBSD.org/Security/. Copyright 2006, The NetBSD Foundation, Inc. All Rights Reserved. Redistribution permitted only in full, unmodified form. $NetBSD: NetBSD-SA2006-003.txt,v 1.8 2006/03/29 21:20:33 adrianp Exp $ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2.2 (NetBSD) iQCVAwUBRCsC4z5Ru2/4N2IFAQIf3gP5ARn8UXOFLz+IMxf5j6HxdEHEv/jMiA7r zzGBT2kTuymM0PRA+KMZMjPfy/KecFz9YTAimQ5hpjSm8xOSah4gyvV3Ojs5gbfF 0QwLZTEzMOoZoVXXn/g5if9wHVi5htZxk0yERGZ5bwWXNW3ybb+/osczRgNXJtjG /N/U1EJ14tY= =agNT -----END PGP SIGNATURE-----