dnsmasq security update

CentOS Errata and Security Advisory CESA-2009:1238

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.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2009-September/078281.html
https://lists.centos.org/pipermail/centos-announce/2009-September/078282.html

Affected packages:
dnsmasq

Upstream details at:
https://access.redhat.com/errata/RHSA-2009:1238