The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. A denial of service flaw was found in the way the dhcpd daemon handled zero-length client identifiers. A remote attacker could use this flaw to send a specially-crafted request to dhcpd, possibly causing it to enter an infinite loop and consume an excessive amount of CPU time. Updated packages are available from ftp.redhat.com.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ===================================================================== Red Hat Security Advisory Synopsis: Moderate: dhcp security update Advisory ID: RHSA-2012:1140-01 Product: Red Hat Enterprise Linux Advisory URL: https://rhn.redhat.com/errata/RHSA-2012-1140.html Issue date: 2012-08-03 CVE Names: CVE-2012-3571 ===================================================================== 1. Summary: Updated dhcp packages that fix one security issue are now available for Red Hat Enterprise Linux 5. The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section. 2. Relevant releases/architectures: RHEL Desktop Workstation (v. 5 client) - i386, x86_64 Red Hat Enterprise Linux (v. 5 server) - i386, ia64, ppc, s390x, x86_64 Red Hat Enterprise Linux Desktop (v. 5 client) - i386, x86_64 3. Description: The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. A denial of service flaw was found in the way the dhcpd daemon handled zero-length client identifiers. A remote attacker could use this flaw to send a specially-crafted request to dhcpd, possibly causing it to enter an infinite loop and consume an excessive amount of CPU time. (CVE-2012-3571) Upstream acknowledges Markus Hietava of the Codenomicon CROSS project as the original reporter of this issue. Users of DHCP should upgrade to these updated packages, which contain a backported patch to correct this issue. After installing this update, all DHCP servers will be restarted automatically. 4. Solution: Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/knowledge/articles/11258 5. Bugs fixed (http://bugzilla.redhat.com/): 842420 - CVE-2012-3571 dhcp: DoS due to error in handling malformed client identifiers 6. Package List: Red Hat Enterprise Linux Desktop (v. 5 client): Source: ftp://ftp.redhat.com/pub/redhat/linux/enterprise/5Client/en/os/SRPMS/dhcp-3.0.5-31.el5_8.1.src.rpm i386: dhclient-3.0.5-31.el5_8.1.i386.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-3.0.5-31.el5_8.1.i386.rpm x86_64: dhclient-3.0.5-31.el5_8.1.x86_64.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.i386.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.x86_64.rpm libdhcp4client-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-3.0.5-31.el5_8.1.x86_64.rpm RHEL Desktop Workstation (v. 5 client): Source: ftp://ftp.redhat.com/pub/redhat/linux/enterprise/5Client/en/os/SRPMS/dhcp-3.0.5-31.el5_8.1.src.rpm i386: dhcp-3.0.5-31.el5_8.1.i386.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.i386.rpm dhcp-devel-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.i386.rpm x86_64: dhcp-3.0.5-31.el5_8.1.x86_64.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.i386.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.x86_64.rpm dhcp-devel-3.0.5-31.el5_8.1.i386.rpm dhcp-devel-3.0.5-31.el5_8.1.x86_64.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.x86_64.rpm Red Hat Enterprise Linux (v. 5 server): Source: ftp://ftp.redhat.com/pub/redhat/linux/enterprise/5Server/en/os/SRPMS/dhcp-3.0.5-31.el5_8.1.src.rpm i386: dhclient-3.0.5-31.el5_8.1.i386.rpm dhcp-3.0.5-31.el5_8.1.i386.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.i386.rpm dhcp-devel-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.i386.rpm ia64: dhclient-3.0.5-31.el5_8.1.ia64.rpm dhcp-3.0.5-31.el5_8.1.ia64.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.ia64.rpm dhcp-devel-3.0.5-31.el5_8.1.ia64.rpm libdhcp4client-3.0.5-31.el5_8.1.ia64.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.ia64.rpm ppc: dhclient-3.0.5-31.el5_8.1.ppc.rpm dhcp-3.0.5-31.el5_8.1.ppc.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.ppc.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.ppc64.rpm dhcp-devel-3.0.5-31.el5_8.1.ppc.rpm dhcp-devel-3.0.5-31.el5_8.1.ppc64.rpm libdhcp4client-3.0.5-31.el5_8.1.ppc.rpm libdhcp4client-3.0.5-31.el5_8.1.ppc64.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.ppc.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.ppc64.rpm s390x: dhclient-3.0.5-31.el5_8.1.s390x.rpm dhcp-3.0.5-31.el5_8.1.s390x.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.s390.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.s390x.rpm dhcp-devel-3.0.5-31.el5_8.1.s390.rpm dhcp-devel-3.0.5-31.el5_8.1.s390x.rpm libdhcp4client-3.0.5-31.el5_8.1.s390.rpm libdhcp4client-3.0.5-31.el5_8.1.s390x.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.s390.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.s390x.rpm x86_64: dhclient-3.0.5-31.el5_8.1.x86_64.rpm dhcp-3.0.5-31.el5_8.1.x86_64.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.i386.rpm dhcp-debuginfo-3.0.5-31.el5_8.1.x86_64.rpm dhcp-devel-3.0.5-31.el5_8.1.i386.rpm dhcp-devel-3.0.5-31.el5_8.1.x86_64.rpm libdhcp4client-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-3.0.5-31.el5_8.1.x86_64.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.i386.rpm libdhcp4client-devel-3.0.5-31.el5_8.1.x86_64.rpm These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from https://access.redhat.com/security/team/key/#package 7. References: https://www.redhat.com/security/data/cve/CVE-2012-3571.html https://access.redhat.com/security/updates/classification/#moderate http://www.isc.org/software/dhcp/advisories/cve-2012-3571 8. Contact: The Red Hat security contact is <email@example.com>. More contact details at https://access.redhat.com/security/team/contact/ Copyright 2012 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.4 (GNU/Linux) iD8DBQFQGyZzXlSAg2UNWIIRAsb0AJ9/TUNO3JmvLmg6hSOz/5UZuqQ68wCcCEJv jupifnoJK/NuU+dLA6j3KpU= =DEre -----END PGP SIGNATURE-----