net security update

CentOS Errata and Security Advisory CESA-2015:2345

The net-snmp packages provide various libraries and tools for the Simple
Network Management Protocol (SNMP), including an SNMP library, an
extensible agent, tools for requesting or setting information from SNMP
agents, tools for generating and handling SNMP traps, a version of the
netstat command which uses SNMP, and a Tk/Perl Management Information Base
(MIB) browser.

A denial of service flaw was found in the way snmptrapd handled certain
SNMP traps when started with the “-OQ” option. If an attacker sent an SNMP
trap containing a variable with a NULL type where an integer variable type
was expected, it would cause snmptrapd to crash. (CVE-2014-3565)

This update also fixes the following bugs:

• Previously, the clientaddr option in the snmp.conf file affected outgoing
  messages sent only over IPv4. With this release, outgoing IPv6 messages are
  correctly sent from the interface specified by clientaddr. (BZ#1190679)

• The Net-SNMP daemon, snmpd, did not properly clean memory when reloading
  its configuration file with multiple “exec” entries. Consequently, the
  daemon terminated unexpectedly. Now, the memory is properly cleaned, and
  snmpd no longer crashes on reload. (BZ#1228893)

• Prior to this update, snmpd did not parse complete IPv4 traffic
  statistics, but reported the number of received or sent bytes in the
  IP-MIB::ipSystemStatsTable only for IPv6 packets and not for IPv4.
  This affected objects ipSystemStatsInOctets, ipSystemStatsOutOctets,
  ipSystemStatsInMcastOctets, and ipSystemStatsOutMcastOctets. Now, the
  statistics reported by snmpd are collected for IPv4 as well. (BZ#1235697)

• The Net-SNMP daemon, snmpd, did not correctly detect the file system
  change from read-only to read-write. Consequently, after remounting the
  file system into the read-write mode, the daemon reported it to be still
  in the read-only mode. A patch has been applied, and snmpd now detects the
  mode changes as expected. (BZ#1241897)

All net-snmp users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-cr-announce/2015-November/028769.html

Affected packages:
net-snmp
net-snmp-agent-libs
net-snmp-devel
net-snmp-gui
net-snmp-libs
net-snmp-perl
net-snmp-python
net-snmp-sysvinit
net-snmp-utils

Upstream details at:
https://access.redhat.com/errata/RHSA-2015:2345