Vulnerability Note VU#4923

Windows NT SNMP agent leaks memory

Overview

The Microsoft SNMP agent, prior to Windows NT 4.0 Service Pack 4.0, will leak memory.

I. Description

Microsoft's SNMP agent, snmp.exe, priot to Windows NT 4.0 Service Pack 4.0, will leak memory if the OID cannot be decoded. Quoting from Microsoft KB article Q178381,

If SNMP cannot decode an OID from a network packet, SNMP does not free up the memory, resulting in a memory leak in the Snmp.exe processes. The impact of this leak will be more evident on a system running on a network segment that receive lots of SNMP broadcast traffic.

An intruder can craft a malicious SNMP packet and consume memory on a victim host.

This problem was addressed by Microsoft in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.

II. Impact

Intruders can consume memory on vulnerable machines, causing denial or degredation of service.

III. Solution

Upgrade to Windows NT service pack 4 or later, as described in http://support.microsoft.com/support/kb/articles/q178/3/81.asp.

Systems Affected

Vendor	Status	Date Updated
Microsoft	Vulnerable	15-Nov-2001

References

http://support.microsoft.com/support/kb/articles/q178/3/81.asp

Credit

Our thanks to Microsoft for the information in their Knowledgebase.

This document was written by Shawn V Hernan.

Other Information

Date Public	03/24/1998
Date First Published	11/15/2001 12:48:43 AM
Date Last Updated	11/15/2001
CERT Advisory
CVE Name
Metric	1.90
Document Revision	5

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