[ GLSA 200909-19 ] Dnsmasq: Multiple vulnerabilities

[GLSA]

Gentoo Linux Security Advisory

Title: Dnsmasq: Multiple vulnerabilities (GLSA 200909-19)
Severity: normal
Exploitable: remote
Date: September 20, 2009
Bug(s): #282653
ID: 200909-19

Synopsis


Multiple vulnerabilities in Dnsmasq might result in the remote execution of
arbitrary code, or a Denial of Service.


Background


Dnsmasq is a lightweight, easy to configure DNS forwarder and DHCP
server. It includes support for Trivial FTP (TFTP).


Affected Packages

Package: net-dns/dnsmasq
Vulnerable: < 2.5.0
Unaffected: >= 2.5.0
Architectures: All supported architectures


Description


Multiple vulnerabilities have been reported in the TFTP functionality
included in Dnsmasq:

• Pablo Jorge and Alberto Solino
  discovered a heap-based buffer overflow (CVE-2009-2957).
• An
  anonymous researcher reported a NULL pointer reference
  (CVE-2009-2958).

Impact


A remote attacker in the local network could exploit these
vulnerabilities by sending specially crafted TFTP requests to a machine
running Dnsmasq, possibly resulting in the remote execution of
arbitrary code with the privileges of the user running the daemon, or a
Denial of Service. NOTE: The TFTP server is not enabled by default.


Workaround


You can disable the TFTP server either at buildtime by not enabling the
"tftp" USE flag, or at runtime. Make sure "--enable-tftp" is not set in
the DNSMASQ_OPTS variable in the /etc/conf.d/dnsmasq file and
"enable-tftp" is not set in /etc/dnsmasq.conf, either of which would
enable TFTP support if it is compiled in.


Resolution


All Dnsmasq users should upgrade to the latest version: