Vulnerability Note VU#681569

Linux Kernel may fail to properly handle SNMP packets

The ip_nat_snmp_basic IP NAT module is intended for use with SNMP network discovery and monitoring applications where target networks use conflicting private IP addresses .

snmp_trap_decode()

The snmp_trap_decode()function decodes v1 and v2 SNMP messages.

The Problem

The function snmp_trap_decode() in the Linux kernel module ip_nat_snmp_basic fails to properly free memory when handling certain SNMP packets.

II. Impact

See the systems affected section of this document for information about specific vendors. Users who compile the Linux kernel from source are encouraged to upgrade to Linux kernel version 2.6.16.18.

Do not use ip_nat_snmp_basic

Do not load the ip_nat_snmp_basic kernel module if it is not needed.

Restrict Access

Limit access to SNMP ports (default 161/udp and 162/udp) to trusted hosts.

Systems Affected

http://secunia.com/advisories/20225/
http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.16.18
http://secunia.com/advisories/20182/

Credit

This vulnerability was reported by Patrick McHardy.

This document was written by Ryan Giobbi.

Other Information

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