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4.112. net-snmp

Updated net-snmp packages that fix one bug are now available for Red Hat Enterprise Linux 5.
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.

Bug Fix

BZ#820850
The SNMP daemon (snmpd) did not properly encode a negative Request-ID in outgoing requests (for example during trap operations). As a consequence, a 32-bit value could be encoded in 5 bytes instead of 4, and the outgoing requests could be refused by some implementations of the SNMP protocol as invalid. With this update, a Request-ID can no longer become negative and is always encoded in 4 bytes.
All users of net-snmp are advised to upgrade to these updated packages, which fix this bug.
Updated net-snmp packages that fix one security issue and multiple bugs are now available for Red Hat Enterprise Linux 5.
The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) associated with each description below.
These packages provide various libraries and tools for the Simple Network Management Protocol (SNMP).

Security Fix

CVE-2012-2141
An out-of-bounds buffer read flaw was found in the net-snmp agent. A remote attacker with read privileges to a Management Information Base (MIB) subtree handled by the "extend" directive (in "/etc/snmp/snmpd.conf") could use this flaw to crash snmpd via a crafted SNMP GET request.

Bug Fix

BZ#754652, BZ#755958, BZ#822061
Devices that used certain file systems were not reported in the "HOST-RESOURCES-MIB::hrStorageTable" table. As a result, the snmpd daemon did not recognize devices using tmpfs, ReiserFS, and Oracle Cluster File System (OCFS2) file systems. This update recognizes these devices and reports them in the "HOST-RESOURCES-MIB::hrStorageTable" table.
BZ#760001
The snmptrapd (8) man page did not correctly describe how to load multiple configuration files using the "-c" option. This update describes correctly that multiple configuration files must be separated by a comma.
BZ#783892
Integers truncated from 64 to 32-bit were not correctly evaluated. As a consequence, the snmpd daemon could enter an endless loop when encoding the truncated integers to network format. This update modifies the underlying code so that snmpd correctly checks truncated 64-bit integers. Now, snmpd avoids an endless loop.
BZ#799699
snmpd did not correctly check for interrupted system calls when enumerating existing IPv6 network prefixes during startup. As a consequence, snmpd could prematurely exit when receiving a signal during this enumeration. This update checks the network prefix enumeration code for interrupted system calls. Now, snmpd no longer terminates when a signal is received.
BZ#803585
snmpd used the wrong length of COUNTER64 values in the AgentX protocol. As a consequence, snmpd could not decode two consecutive COUNTER64 values in one AgentX packet. This update uses the correct COUNTER64 size and can process two or mode COUNTER64 values in AgentX communication.
BZ#805689
snmpd ignored the "-e" parameter of the "trapsess" option in the snmpd configuration file. As a result, outgoing traps were incorrectly sent with the default EngineID of snmpd when configuring "trapsess" with an explicit EngineID. This update modifies the underlying code to send outgoing traps using the EngineID as specified in the "trapsess -e" parameter in the configuration file.
BZ#818259
snmpd did not correctly encode negative Request-IDs in outgoing requests, for example during trap operations. As a consequence, a 32-bit value could be encoded in 5 bytes instead of 4, and the outgoing requests were refused by certain implementations of the SNMP protocol as invalid. With this update, a Request-ID can no longer become negative and is always encoded in 4 bytes.
BZ#828691
snmpd ignored the port number of the "clientaddr" option when specifying the source address of outgoing SNMP requests. As a consequence, the system assigned a random address. This update allows to specify both the port number and the source IP address in the "clientaddr" option. Now, administrators can increase security with firewall rules and Security-Enhanced Linux (SELinux) policies by configuring a specific source port of outgoing traps and other requests.
BZ#830042
snmpd did not correctly process responses to internal queries when initializing monitoring enabled by the "monitor" option in the "/etc/snmp/snmpd.conf" configuration file. As a consequence, snmpd was not fully initialized and the error message "failed to run mteTrigger query" appeared in the system log 30 seconds after the snmpd startup. This update explicitly checks for responses to internal monitoring queries.
Users of net-snmp should upgrade to these updated packages, which contain backported patches to correct these issues. After installing the update, the snmpd and snmptrapd daemons will be restarted automatically.