-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 NetBSD Security Advisory 2013-005 ================================= Topic: bind Denial of Service (CVE-2013-4854) Version: NetBSD-current: source prior to July 28th, 2013 NetBSD 6.1: affected NetBSD 6.0: affected NetBSD 5.2: affected NetBSD 5.1: affected Severity: Denial of Service Fixed: NetBSD-current: July 27th, 2013 NetBSD-6-0 branch: July 29th, 2013 NetBSD-6-1 branch: July 29th, 2013 NetBSD-6 branch: July 29th, 2013 NetBSD-5-2 branch: July 29th, 2013 NetBSD-5-1 branch: July 29th, 2013 NetBSD-5 branch: July 29th, 2013 Please note that NetBSD releases prior to 5.1 are no longer supported. It is recommended that all users upgrade to a supported release. Abstract ======== A specially crafted query that includes malformed rdata can cause named to terminate with an assertion failure while rejecting the malformed query. This vulnerability has been assigned CVE-2013-4854. Technical Details ================= Authoritative and recursive servers are equally vulnerable. Intentional exploitation of this condition can cause a denial of service in nameservers running affected versions of BIND 9. BIND Access Control Lists do not provide any protection from malicious clients. In addition to the named server, applications built using libdns from the affected source distributions may crash with assertion failures triggered in the same fashion. Solutions and Workarounds ========================= If feasible, as a workaround, restrict access to the nameserver to only trusted clients via a packet filter. Solutions: - - Install and use a bind package from pkgsrc. - - Update libdns from a daily build later than the fix date: fetch from http://nyftp.NetBSD.org/pub/NetBSD-daily/<branch>/<date>/<arch>/ the file binary/sets/base.tgz for NetBSD 5.x: cd / && tar xzpf <base.tgz-path> ./usr/lib/libdns.so.1.4 if your arch has 32bit-compat, update the compat lib as well, e.g. for amd64: cd / && tar xzpf <base.tgz-path> ./usr/lib/i386/libdns.so.1.4 for NetBSD 6.x: cd / && tar xzpf <base.tgz-path> ./usr/lib/libdns.so.5.8 if your arch has 32bit-compat, update the compat lib as well, e.g. for amd64: cd / && tar xzpf <base.tgz-path> ./usr/lib/i386/libdns.so.5.8 - - Rebuild your system with the fixes applied. The wrong bounds checking is in bind's lib/dns/rdata/generic/keydata_65533.c Fixed versions: current: src/external/bsd/bind/dist/lib/dns/rdata/generic/keydata_65533.c 1.6 netbsd-6: src/external/bsd/bind/dist/lib/dns/rdata/generic/keydata_65533.c 1.3.4.2 netbsd-6-1: src/external/bsd/bind/dist/lib/dns/rdata/generic/keydata_65533.c 1.3.4.1.6.1 netbsd-6-0: src/external/bsd/bind/dist/lib/dns/rdata/generic/keydata_65533.c 1.3.4.1.4.1 netbsd-5: src/dist/bind/lib/dns/rdata/generic/keydata_65533.c 1.1.2.4 netbsd-5-2: src/dist/bind/lib/dns/rdata/generic/keydata_65533.c 1.1.2.3.2.1 netbsd-5-1: src/dist/bind/lib/dns/rdata/generic/keydata_65533.c 1.1.4.5 Thanks To ========= Thanks to Maxim Shudrak and the HP Zero Day Initiative for reporting this issue and the ISC security team for their advisory (https://kb.isc.org/article/AA-01015). Revision History ================ 2013-07-30 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 http://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2013-005.txt.asc Information about NetBSD and NetBSD security can be found at http://www.NetBSD.org/ and http://www.NetBSD.org/Security/ . Copyright 2013, The NetBSD Foundation, Inc. All Rights Reserved. Redistribution permitted only in full, unmodified form. $NetBSD: NetBSD-SA2013-005.txt,v 1.2 2013/07/30 20:44:22 tonnerre Exp $ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJR+CX5AAoJEAZJc6xMSnBukpUQAJC3dydlOI9KumiZfQUa+MZ/ GPVFNkfSLXMqujJdsB12bE1oT4Oeu4ylSadtCZWgPyiaXZ46uEkFgPODU88JxdAr z4ha31LoFEU+WRSPWeSgJdnX5IHvsyrSzXXoOZc0K99nVRIF67ecgAGHNkxmvghv /zsxfJrAabbdInpX0BzDmu/KE2AlATY7KFAZigqAJH80JAIJ7tAAmnrzfVOD2jXx FGEok/Cz3bAoEUfPG5S77OKAKrq5BmJ9iyfqLd7Hv2vZucBVyPe0FaYAKFsseevI KkHcf9cHPgUiqCsBGnKD1+qL1oV15gAlshhcHUAl+pn7QhsKwJGebKy5ZmeWYy4i WfkH8XMHKKJGvZBxRkqCZNmMmyby6NxSiV1xAMCsiClDVxOoxApMkF8dDsSVUBoJ kE16/x9A3A11kizCaC0+OagezJAsOpHWqyLncIcZN1fJ+mzWFfm7eWnY9GDE22wV 26NNGhMi0AZvBvhFVqjs8GYzc50BYjMYdqWkL+FrITkofTWeGuO7QXujDGdIYsPJ nTNUASMqcvXp9vLkXPLssV4nf3eks1kuaGDM+AdaDkFiH8pj6dVofiYkJeRCobtV jJAc9h8xgm1Rr8h6eqQi14R+DVxt6H5Em10brQrufM16xglmhFoyb1JBm/2FDztw ifNWNjfA+euXhJBVue3b =oGEr -----END PGP SIGNATURE-----