Dnsmasq is a lightweight and easy to configure DNS forwarder and DHCP server. Core Security Technologies discovered a heap overflow flaw in dnsmasq when the TFTP service is enabled that could crash or, possibly, execute arbitrary code with the privileges of the dnsmasq service. A NULL pointer dereference flaw was discovered in dnsmasq when the TFTP service is enabled. This flaw could allow a malicious TFTP client to crash the dnsmasq service. Updated packages are available from updates.redhat.com.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ===================================================================== Red Hat Security Advisory Synopsis: Important: dnsmasq security update Advisory ID: RHSA-2009:1238-01 Product: Red Hat Enterprise Linux Advisory URL: https://rhn.redhat.com/errata/RHSA-2009-1238.html Issue date: 2009-08-31 CVE Names: CVE-2009-2957 CVE-2009-2958 ===================================================================== 1. Summary: An updated dnsmasq package that fixes two security issues is now available for Red Hat Enterprise Linux 5. This update has been rated as having important security impact by the Red Hat Security Response Team. 2. Relevant releases/architectures: Red Hat Enterprise Linux Desktop (v. 5 client) - i386, x86_64 Red Hat Enterprise Linux (v. 5 server) - i386, ia64, ppc, s390x, x86_64 3. Description: Dnsmasq is a lightweight and easy to configure DNS forwarder and DHCP server. Core Security Technologies discovered a heap overflow flaw in dnsmasq when the TFTP service is enabled (the "--enable-tftp" command line option, or by enabling "enable-tftp" in "/etc/dnsmasq.conf"). If the configured tftp-root is sufficiently long, and a remote user sends a request that sends a long file name, dnsmasq could crash or, possibly, execute arbitrary code with the privileges of the dnsmasq service (usually the unprivileged "nobody" user). (CVE-2009-2957) A NULL pointer dereference flaw was discovered in dnsmasq when the TFTP service is enabled. This flaw could allow a malicious TFTP client to crash the dnsmasq service. (CVE-2009-2958) Note: The default tftp-root is "/var/ftpd", which is short enough to make it difficult to exploit the CVE-2009-2957 issue; if a longer directory name is used, arbitrary code execution may be possible. As well, the dnsmasq package distributed by Red Hat does not have TFTP support enabled by default. All users of dnsmasq should upgrade to this updated package, which contains a backported patch to correct these issues. After installing the updated package, the dnsmasq service must be restarted for the update to take effect. 4. Solution: Before applying this update, make sure that all previously-released errata relevant to your system have been applied. This update is available via Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at http://kbase.redhat.com/faq/docs/DOC-11259 5. Bugs fixed (http://bugzilla.redhat.com/): 519020 - CVE-2009-2957, CVE-2009-2958 dnsmasq: multiple vulnerabilities in TFTP server 6. Package List: Red Hat Enterprise Linux Desktop (v. 5 client): Source: ftp://ftp.redhat.com/pub/redhat/linux/enterprise/5Client/en/os/SRPMS/dnsmasq-2.45-1.1.el5_3.src.rpm i386: dnsmasq-2.45-1.1.el5_3.i386.rpm dnsmasq-debuginfo-2.45-1.1.el5_3.i386.rpm x86_64: dnsmasq-2.45-1.1.el5_3.x86_64.rpm dnsmasq-debuginfo-2.45-1.1.el5_3.x86_64.rpm Red Hat Enterprise Linux (v. 5 server): Source: ftp://ftp.redhat.com/pub/redhat/linux/enterprise/5Server/en/os/SRPMS/dnsmasq-2.45-1.1.el5_3.src.rpm i386: dnsmasq-2.45-1.1.el5_3.i386.rpm dnsmasq-debuginfo-2.45-1.1.el5_3.i386.rpm ia64: dnsmasq-2.45-1.1.el5_3.ia64.rpm dnsmasq-debuginfo-2.45-1.1.el5_3.ia64.rpm ppc: dnsmasq-2.45-1.1.el5_3.ppc.rpm dnsmasq-debuginfo-2.45-1.1.el5_3.ppc.rpm s390x: dnsmasq-2.45-1.1.el5_3.s390x.rpm dnsmasq-debuginfo-2.45-1.1.el5_3.s390x.rpm x86_64: dnsmasq-2.45-1.1.el5_3.x86_64.rpm dnsmasq-debuginfo-2.45-1.1.el5_3.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://www.redhat.com/security/team/key/#package 7. References: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-2957 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-2958 http://www.redhat.com/security/updates/classification/#important 8. Contact: The Red Hat security contact is <firstname.lastname@example.org>. More contact details at https://www.redhat.com/security/team/contact/ Copyright 2009 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.4 (GNU/Linux) iD8DBQFKnGj+XlSAg2UNWIIRAqlbAJ4obBBc7erzPdu46+OD7GpyjNLnswCcCjii r+XXPtJj1i9ZsL+6ADBu2tQ= =YGeD -----END PGP SIGNATURE-----