Vulnerability Note VU#681569

Linux Kernel may fail to properly handle SNMP packets

Original Release date: 09 Jun 2006 | Last revised: 13 Jul 2006


A memory freeing vulnerability in the Linux kernel module ip_nat_snmp_basic can be exploited to create a denial-of-service condition.



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 .


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.


A remote attacker could cause a system running Linux kernel version < with the ip_nat_snmp_basic module loaded to crash. This results in a denial-of-service condition.


Apply an update
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

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 (Learn More)

VendorStatusDate NotifiedDate Updated
Mandriva, Inc.Affected-09 Jun 2006
Trustix Secure LinuxAffected-09 Jun 2006
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



This vulnerability was reported by Patrick McHardy.

This document was written by Ryan Giobbi.

Other Information

  • CVE IDs: CVE-2006-2444
  • Date Public: 23 May 2006
  • Date First Published: 09 Jun 2006
  • Date Last Updated: 13 Jul 2006
  • Severity Metric: 2.69
  • Document Revision: 21


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