Red Hat Enterprise Linux 7 RHSA-2015:2345-01 Moderate: net-snmp DoS

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.