Scientific Linux Security Update : net-snmp on SL5.x i386/x86_64

This script is Copyright (C) 2013 Tenable Network Security, Inc.


Synopsis :

The remote Scientific Linux host is missing one or more security
updates.

Description :

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. (CVE-2012-2141)

Bug fixes :

- 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.

- 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.

- 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.

- 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.

- 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.

- 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.

- 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.

- 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.

- 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.

After installing the update, the snmpd and snmptrapd daemons will be
restarted automatically.

See also :

http://www.nessus.org/u?1188b02b

Solution :

Update the affected packages.

Risk factor :

Low / CVSS Base Score : 3.5
(CVSS2#AV:N/AC:M/Au:S/C:N/I:N/A:P)

Family: Scientific Linux Local Security Checks

Nessus Plugin ID: 63600 ()

Bugtraq ID:

CVE ID: CVE-2012-2141