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Microsoft Windows DCOM RPC Interface Buffer Overrun Vulnerability

Risk
High

Date Discovered
07-16-2003

Description
A buffer overrun vulnerability has been reported in Microsoft Windows that can be exploited remotely via a DCOM RPC interface that listens on TCP/UDP port 135. The issue is due to insufficient bounds checking of client DCOM object activation requests. Exploitation of this issue could result in execution of malicious instructions with Local System privileges on an affected system.

This issue may be exposed on other ports that the RPC Endpoint Mapper listens on, such as TCP ports 139, 135, 445 and 593. This has not been confirmed. Under some configurations the Endpoint Mapper may receive traffic via port 80.

Update
7-31-2003: Although spikes in activity have been reported during the past five days, the majority of this scanning activity appears to be isolated to a small number of hosts. Exploit development is continuing, but at this time there is no evidence that successful worms have been developed. Although the level of activity on this port has been climbing steadily since the announcement of the vulnerability a few weeks ago, organizations that have robust filtering, and frequent patch auditing should be relatively safe.

Enterprise Security Manager
Symantec has posted an Enterprise Security Manager™ Response Policy for this vulnerability. It is available here.

Norton Internet Security / Norton Internet Security Professional
Symantec has released an update for these products, via LiveUpdate, to detect this vulnerability. Users of these products should run LiveUpdate to ensure protection against this threat.

Symantec Client Firewall
Symantec has released an update for Symantec Client Firewall to detect attempts to exploit this vulnerability. Symantec Client Firewall users should run LiveUpdate to ensure protection against this threat.

Symantec Client Security
Symantec has released an update for Symantec Client Security to detect attempts to exploit this vulnerability. Symantec Client Security users should run LiveUpdate to ensure protection against this threat.

Symantec Enterprise Firewall
Symantec's full application inspection firewall technology protects against this Microsoft vulnerability, blocking all the above listed TCP ports by default. For Windows-based firewalls, unique initial and ongoing system hardening automatically protects the firewall itself from this RPC-based attack. For maximum security, 3rd generation full application inspection technology intelligently blocks tunneling of DCOM traffic over HTTP channels thus providing an extra layer of protection not readily available on most common network filtering firewalls.

Symantec Gateway Security
Symantec has released an update for Symantec Gateway Security, via LiveUpdate, to detect this vulnerability. Symantec Gateway Security users should run LiveUpdate to ensure protection against this threat.

Symantec ManHunt 3.0
Symantec has released a Security Update for users of Symantec Manhunt 3.0. Click here for more information.

Symantec Vulnerability Assessment
Symantec Vulnerability Assessment detects and reports this vulnerability. Click here for further information.

Symantec NetRecon
Symantec NetRecon detects and reports this vulnerability. Refer to Symantec NetRecon SU6 for more details.

Components Affected
Microsoft Windows 2000 Advanced Server SP4
Microsoft Windows 2000 Advanced Server SP3
Microsoft Windows 2000 Advanced Server SP2
Microsoft Windows 2000 Advanced Server SP1
Microsoft Windows 2000 Advanced Server
Microsoft Windows 2000 Datacenter Server SP4
Microsoft Windows 2000 Datacenter Server SP3
Microsoft Windows 2000 Datacenter Server SP2
Microsoft Windows 2000 Datacenter Server SP1
Microsoft Windows 2000 Datacenter Server
Microsoft Windows 2000 Professional SP4
Microsoft Windows 2000 Professional SP3
Microsoft Windows 2000 Professional SP2
Microsoft Windows 2000 Professional SP1
Microsoft Windows 2000 Professional
Microsoft Windows 2000 Server SP4
Microsoft Windows 2000 Server SP3
Microsoft Windows 2000 Server SP2
Microsoft Windows 2000 Server SP1
Microsoft Windows 2000 Server
Microsoft Windows NT Enterprise Server 4.0 SP6a
Microsoft Windows NT Enterprise Server 4.0 SP6
Microsoft Windows NT Enterprise Server 4.0 SP5
Microsoft Windows NT Enterprise Server 4.0 SP4
Microsoft Windows NT Enterprise Server 4.0 SP3
Microsoft Windows NT Enterprise Server 4.0 SP2
Microsoft Windows NT Enterprise Server 4.0 SP1
Microsoft Windows NT Enterprise Server 4.0
Microsoft Windows NT Server 4.0 SP6a
Microsoft Windows NT Server 4.0 SP6
Microsoft Windows NT Server 4.0 SP5
Microsoft Windows NT Server 4.0 SP4
Microsoft Windows NT Server 4.0 SP3
Microsoft Windows NT Server 4.0 SP2
Microsoft Windows NT Server 4.0 SP1
Microsoft Windows NT Server 4.0
Microsoft Windows NT Terminal Server 4.0 SP6a
Microsoft Windows NT Terminal Server 4.0 SP6
Microsoft Windows NT Terminal Server 4.0 SP5
Microsoft Windows NT Terminal Server 4.0 SP4
Microsoft Windows NT Terminal Server 4.0 SP3
Microsoft Windows NT Terminal Server 4.0 SP2
Microsoft Windows NT Terminal Server 4.0 SP1
Microsoft Windows NT Terminal Server 4.0
Microsoft Windows NT Workstation 4.0 SP6a
Microsoft Windows NT Workstation 4.0 SP6
Microsoft Windows NT Workstation 4.0 SP5
Microsoft Windows NT Workstation 4.0 SP4
Microsoft Windows NT Workstation 4.0 SP3
Microsoft Windows NT Workstation 4.0 SP2
Microsoft Windows NT Workstation 4.0 SP1
Microsoft Windows NT Workstation 4.0
Microsoft Windows Server 2003 Datacenter Edition
Microsoft Windows Server 2003 Datacenter Edition 64-bit
Microsoft Windows Server 2003 Enterprise Edition
Microsoft Windows Server 2003 Enterprise Edition 64-bit
Microsoft Windows Server 2003 Standard Edition
Microsoft Windows Server 2003 Web Edition
Microsoft Windows XP 64-bit Edition SP1
Microsoft Windows XP 64-bit Edition
Microsoft Windows XP Home SP1
Microsoft Windows XP Home
Microsoft Windows XP Professional SP1
Microsoft Windows XP Professional

Recommendations
Block external access at the network boundary, unless service is required by external parties.
Hosts that can send malicious traffic to TCP port 135 can exploit this issue. External access to this port should be filtered at network perimeters. Permit access for trusted or internal hosts and networks only.

Implement multiple redundant layers of security.
Multiple layers of network access control and intrusion detection should be deployed to limit exposure to potentially vulnerable systems and monitor network traffic for malicious or anomalous activity.

Microsoft has released patches to address this issue:


Microsoft Windows 2000 Advanced Server SP4:

Microsoft Patch Windows2000-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=C8B8A846-F541-4C15-8C9F-220354449117&displaylang=en

Microsoft Windows 2000 Advanced Server SP3:
Microsoft Patch Windows2000-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=C8B8A846-F541-4C15-8C9F-220354449117&displaylang=en

Microsoft Windows 2000 Advanced Server SP2:
Microsoft Windows 2000 Datacenter Server SP4:
Microsoft Windows 2000 Datacenter Server SP3:
Microsoft Windows 2000 Datacenter Server SP2:
Microsoft Windows 2000 Professional SP4:
Microsoft Patch Windows2000-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=C8B8A846-F541-4C15-8C9F-220354449117&displaylang=en

Microsoft Windows 2000 Professional SP3:
Microsoft Patch Windows2000-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=C8B8A846-F541-4C15-8C9F-220354449117&displaylang=en

Microsoft Windows 2000 Professional SP2:
Microsoft Windows 2000 Server SP4:
Microsoft Patch Windows2000-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=C8B8A846-F541-4C15-8C9F-220354449117&displaylang=en

Microsoft Windows 2000 Server SP3:
Microsoft Patch Windows2000-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=C8B8A846-F541-4C15-8C9F-220354449117&displaylang=en

Microsoft Windows 2000 Server SP2:
Microsoft Windows NT Enterprise Server 4.0 SP6a:
Microsoft Patch Q823980i.EXE
http://microsoft.com/downloads/details.aspx?FamilyId=2CC66F4E-217E-4FA7-BDBF-DF77A0B9303F&displaylang=en

Microsoft Windows NT Server 4.0 SP6a:
Microsoft Patch Q823980i.EXE
http://microsoft.com/downloads/details.aspx?FamilyId=2CC66F4E-217E-4FA7-BDBF-DF77A0B9303F&displaylang=en

Microsoft Windows NT Terminal Server 4.0 SP6a:
Microsoft Patch Q823980i.EXE
http://microsoft.com/downloads/details.aspx?FamilyId=6C0F0160-64FA-424C-A3C1-C9FAD2DC65CA&displaylang=en

Microsoft Windows NT Workstation 4.0 SP6a:
Microsoft Patch Q823980i.EXE
http://microsoft.com/downloads/details.aspx?FamilyId=2CC66F4E-217E-4FA7-BDBF-DF77A0B9303F&displaylang=en

Microsoft Windows Server 2003 Datacenter Edition :
Microsoft Windows Server 2003 Datacenter Edition 64-bit :
Microsoft Windows Server 2003 Enterprise Edition :
Microsoft Patch WindowsServer2003-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=F8E0FF3A-9F4C-4061-9009-3A212458E92E&displaylang=en

Microsoft Windows Server 2003 Enterprise Edition 64-bit :
Microsoft Patch WindowsServer2003-KB823980-ia64-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=2B566973-C3F0-4EC1-995F-017E35692BC7&displaylang=en

Microsoft Windows Server 2003 Standard Edition :
Microsoft Patch WindowsServer2003-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=F8E0FF3A-9F4C-4061-9009-3A212458E92E&displaylang=en

Microsoft Windows Server 2003 Web Edition :
Microsoft Patch WindowsServer2003-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=F8E0FF3A-9F4C-4061-9009-3A212458E92E&displaylang=en

Microsoft Windows XP 64-bit Edition SP1:
Microsoft Patch WindowsXP-KB823980-ia64-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=1B00F5DF-4A85-488F-80E3-C347ADCC4DF1&displaylang=en

Microsoft Windows XP 64-bit Edition :
Microsoft Windows XP Home SP1:
Microsoft Patch WindowsXP-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=2354406C-C5B6-44AC-9532-3DE40F69C074&displaylang=en

Microsoft Windows XP Home :
Microsoft Windows XP Professional SP1:
Microsoft Patch WindowsXP-KB823980-x86-ENU.exe
http://microsoft.com/downloads/details.aspx?FamilyId=2354406C-C5B6-44AC-9532-3DE40F69C074&displaylang=en

Microsoft Windows XP Professional :

References
Source: Microsoft Security Bulletin MS03-026
URL: http://www.microsoft.com/technet/treeview/default.asp?url=/technet/security/bulletin/MS03-026.asp

Credits
Discovery of this vulnerability has been credited to The Last Stage of Delirium Research Group.


Copyright (c) 2003 by Symantec Corp.
Permission to redistribute this alert electronically is granted as long as it is not edited in any way unless authorized by Symantec Security Response. Reprinting the whole or part of this alert in any medium other than electronically requires permission from symsecurity@symantec.com.

Disclaimer
The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.

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