|
Brought to you by:
Suppliers of:
|
|
|
| |
| Multiple vulnerabilities have been discovered in Windows' MSDTC and COM+, the following advisory summarizes 4 of them. |
| |
Credit:
The information has been provided by Microsoft Product Security.
The original article can be found at: http://www.microsoft.com/technet/security/bulletin/MS05-051.mspx
|
| |
Affected Software:
* Microsoft Windows 2000 Service Pack 4 - Download the update
* Microsoft Windows XP Service Pack 1 and Microsoft Windows XP Service Pack 2 - Download the update
* Microsoft Windows XP Professional x64 Edition - Download the update
* Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1 - Download the update
* Microsoft Windows Server 2003 for Itanium-based Systems and Microsoft Windows Server 2003 with SP1 for Itanium-based Systems - Download the update
* Microsoft Windows Server 2003 x64 Edition - Download the update
Non-Affected Software:
* Microsoft Windows 98, Microsoft Windows 98 Second Edition (SE), and Microsoft Windows Millennium Edition (ME)
MSDTC Vulnerability:
A remote code execution and local elevation of privilege vulnerability exists in the Microsoft Distributed Transaction Coordinator that could allow an attacker who successfully exploited this vulnerability to take complete control of the affected system.
CVE Information:
CAN-2005-2119
Mitigating Factors for MSDTC Vulnerability:
* Windows XP Service Pack 2 and Windows Server 2003 Service Pack 1 systems are not vulnerable to this issue.
* By default, on Windows Server 2003, the Microsoft Distributed Transaction Coordinator is started, but it is not configured to support Network DTC Access. An attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability. However, if an administrator has enabled support for Network DTC Access, Windows Server 2003 systems could be vulnerable to remote code execution attacks by anonymous users. For information about how to configure Network DTC Access, visit the following Microsoft Web site.
* By default, on Windows XP Service Pack 1, the Microsoft Distributed Transaction Coordinator is not started. This service must be running to enable the remote attack vector. An attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability. However, any local user can start this service unless the service has been disabled by an administrator. As soon as this service is started, Windows XP Service Pack 1 systems could be vulnerable to remote code execution attacks by anonymous users. This is because on Windows XP Service Pack 1 systems, the Microsoft Distributed Transaction Coordinator service is configured to allow Network DTC Access. For information about how to configure Network DTC Access, visit the following Microsoft Web site.
* For customers who require the affected component, firewall best practices and standard default firewall configurations can help protect networks from attacks that originate outside the enterprise perimeter. Best practices recommend that systems that are connected to the Internet have a minimal number of ports exposed.
Workarounds for MSDTC Vulnerability:
Microsoft has tested the following workarounds. While these workarounds will not correct the underlying vulnerability, they help block known attack vectors. When a workaround reduces functionality, it is identified in the following section.
* Disable the Distributed Transaction Coordinator
Disabling the Distributed Transaction Coordinator helps protect the affected system from attempts to exploit this vulnerability. To disable the Distributed Transaction Coordinator, follow these steps:
1. Click Start, and then click Control Panel. Alternatively, click Start, point to Settings, and then click Control Panel.
2. Double-click Administrative Tools.
3. Double-click Component Services.
4. Click Services.
5. Double-click Distributed Transaction Coordinator.
6. In the Startup type list, click Disabled.
7. Click Stop, and then click OK.
You can also stop and disable the Distributed Transaction Coordinator by using the following command at the command prompt:
sc stop MSDTC & sc config MSDTC start= disabled
Impact of Workaround: If you disable the Distributed Transaction Coordinator, you cannot use any service or application that is dependant on the Distributed Transaction Coordinator. This could include other applications such as SQL Server, BizTalk Server, Exchange Server, or Message Queuing. Also, this service is required in most clustering configurations. Therefore, we recommend this workaround only on systems that cannot install the security update.
* Use the Group Policy settings to disable the Distributed Transaction Coordinator on all affected systems that do not require this feature.
Because the Distributed Transaction Coordinator is a possible attack vector, disable it by using the Group Policy settings. You can disable the startup of this service at the local, site, domain, or organizational unit level by using Group Policy object functionality in Windows 2000 domain environments or in Windows Server 2003 domain environments. For more information about how to disable this service through logon scripts, see Microsoft Knowledge Base Article 297789
Note You may also review the Windows 2000 Security Hardening Guide. This guide includes information about how to disable services.
For more information about Group Policy, visit the following Web sites:
o Step-by-Step Guide to Understanding the Group Policy Feature Set
o Windows 2000 Group Policy
o Group Policy in Windows Server 2003
Impact of Workaround: If you disable the Distributed Transaction Coordinator, you cannot use any service or application that is dependant on the Distributed Transaction Coordinator. This could include other applications such as SQL Server, BizTalk Server, Exchange Server, or Message Queuing. Also, this service is required in most clustering configurations. Therefore, we recommend this workaround only on systems that cannot install the security update.
* Disable Network DTC Access
If you cannot install the security update, and you cannot disable the Distributed Transaction Coordinator, you may want to disable Network DTC Access. This option is only available on Windows XP and later operating system versions. This still allows local transactions to complete, but it helps protect from network based attacks that try to exploit this issue. For information about how to configure Network DTC Access, visit the following Microsoft Web site. To disable Network DTC Access, follow these steps:
Warning Performing this procedure causes the affected service to start if it was not started previously. Stop the MSDTC service on the MSDTC tab before you close the configuration dialog boxes.
1. Click Start, and then click Control Panel. Alternatively, click Start, point to Settings, and then click Control Panel.
2. Double-click Administrative Tools.
3. Double-Click Component Services, expand Component Services, expand Computers, right-click My Computer and then click Properties,
4. Click the MSDTC tab, and then click Security Configuration.
5. In the Security Configuration dialog box, click to clear the Network DTC Access check box.
Note This sets the following DWORD registry entry to 0 on non-clustering environments. Clustering environments do not read the following registry key. For Clustering environments, follow the steps that are listed in the Disable the Distributed Transaction Coordinator bullet point.
HKLM\Software\Microsoft\MSDTC\Security\NetworkDtcAccess
Note You can also apply this setting to multiple systems by using Group Policy. For more information about Group Policy, visit the following Microsoft Web site.
6. Click OK, close the Component Services dialog box, and then close the Administrative Tools dialog box.
Impact of Workaround: If you disable Network DTC Access, distributed transaction could fail. This could impact other applications such as SQL Server, BizTalk Server, or Message Queuing. Therefore, we recommend this workaround only on systems that cannot install the security update.
* Block the following at the firewall:
o All unsolicited inbound traffic on ports greater than 1024
o Any other specifically configured RPC port
These ports can be used to initiate a connection with MSDTC. Blocking them at the firewall will help protect systems that are behind that firewall from attempts to exploit this vulnerability. Also, make sure that you block any other specifically-configured RPC port on the remote system. We recommend that you block all unsolicited inbound communication from the Internet to help prevent attacks that may use other ports. While RPC can use UDP ports 135, 137, 138, 445, and TCP ports 135, 139, 445, and 593, the MSDTC service is not vulnerable over those ports.
Note Other protocols, such as Sequenced Packet Exchange (SPX) or NetBEUI, could be used to communicate with the MSDTC service. If you are using these protocols, you should block the appropriate ports for those protocols. For more information about IPX and SPX, visit the following Microsoft Web site.
* To help protect from network-based attempts to exploit this vulnerability, use a personal firewall, such as the Internet Connection Firewall, which is included with Windows XP and with Windows Server 2003.
By default, the Internet Connection Firewall feature in Windows XP and in Windows Server 2003 helps protect your Internet connection by blocking unsolicited incoming traffic. We recommend that you block all unsolicited incoming communication from the Internet.
To enable the Internet Connection Firewall feature by using the Network Setup Wizard, follow these steps:
1. Click Start, and then click Control Panel.
2. In the default Category View, click Network and Internet Connections, and then click Setup or change your home or small office network. The Internet Connection Firewall feature is enabled when you select a configuration in the Network Setup Wizard that indicates that your system is connected directly to the Internet.
To configure Internet Connection Firewall manually for a connection, follow these steps:
1. Click Start, and then click Control Panel.
2. In the default Category View, click Networking and Internet Connections, and then click Network Connections. (Windows Sever 2003 displays this as Network Connections)
3. Right-click the connection on which you want to enable Internet Connection Firewall, and then click Properties.
4. Click the Advanced tab.
5. Under Windows Firewall, click Settings.
6. Click On, and then click OK.
7. Click the Exceptions tab. You may need to click Settings to display the exceptions tab.
8. Verify that MSDTC.exe is not in the list of firewall exceptions, and then click OK.
Note If you want to enable certain programs and services to communicate through the firewall, click Settings on the Advanced tab, and then select the programs, the protocols, and the services that are required.
* To help protect from network-based attempts to exploit this vulnerability, enable advanced TCP/IP filtering on systems that support this feature.
You can enable advanced TCP/IP filtering to block all unsolicited inbound traffic. For more information about how to configure TCP/IP filtering, see Microsoft Knowledge Base Article 309798.
* To help protect from network-based attempts to exploit this vulnerability, block the affected ports by using IPsec on the affected systems.
Use Internet Protocol security (IPsec) to help protect network communications. Detailed information about IPsec and about how to apply filters is available in Microsoft Knowledge Base Article 313190 and Microsoft Knowledge Base Article 813878. RPC uses a broad range of ports, which may make it difficult to try to secure them all by using IPsec. Microsoft Knowledge Base Article 908472 documents how to restrict RPC communication to a set of fixed ports and how to secure those ports by using IPsec.
FAQ for MSDTC Vulnerability:
What is the scope of the vulnerability?
On Windows 2000 this is a remote code execution vulnerability. On Windows XP Service Pack 1 and Windows Server 2003 this is a local privilege elevation vulnerability. On Windows XP Service Pack 1, this also becomes a remote code execution vulnerability if the Microsoft Distributed Transaction Coordinator is started. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
An unchecked buffer in the Microsoft Distributed Transaction Coordinator.
What is the Microsoft Distributed Transaction Coordinator?
The Microsoft Distributed Transaction Coordinator (MSDTC) is a distributed transaction facility for Microsoft Windows platforms. MSDTC uses proven transaction processing technology. It is robust despite system failures, process failures, and communication failures; it exploits loosely coupled systems to provide scalable performance; and it is easy to install, configure, and manage. The DTC service provides the following benefits:
* Reduces the cost of enterprise computing.
The DTC provides a sophisticated, low-cost distributed transaction facility for users of networked, commodity-priced PCs and servers.
* Simplifies application development.
DTC transactions greatly simplify the application task of preserving consistency, despite failures that can occur when updating application data.
* Provides a consistent transaction model.
The DTC supports a variety of resource managers, including relational databases, object-oriented databases, file systems, document storage systems, and message queues.
* Enables software development using distributed software components.
The DTC provides a simple, object-oriented application programming interface for initiating and controlling transactions.
For information about MSDTC, visit the following Microsoft Web site.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could take complete control of the affected system.
Who could exploit the vulnerability?
On Windows 2000, any anonymous user who could deliver a specially crafted network message to the affected system could try to exploit this vulnerability. On Windows XP Service Pack 1 and Windows Server 2003, an attacker must be able to log on locally to a system and run a program to try to exploit the vulnerability. Windows XP Service Pack 1 and Windows Server 2003 are not vulnerable to remote anonymous attack in default scenarios. User configuration is required on these operating system versions in order to create the possibility of remote attack. If attacked locally, an attacker could then run a specially-crafted application that could exploit the vulnerability and gain complete control over the affected system.
What systems are primarily at risk from the vulnerability?
Windows 2000 systems are primarily at risk from this vulnerability. On Windows XP Service Pack 1 and Windows Server 2003, an attacker must have valid logon credentials to exploit this vulnerability unless user configuration has been performed that could allow remote anonymous attacks. On Windows Server 2003, if an administrator has enabled support for Network DTC Access, Windows Server 2003 systems could be vulnerable to remote code execution attacks by anonymous users. For information about how to configure Network DTC Access, visit the following Microsoft Web site. Administrators can use the registry key that is documented at the following Microsoft Web site to verify that Network DTC Access has not been enabled.
Could the vulnerability be exploited over the Internet?
On Windows 2000 an attacker could try to exploit this vulnerability over the Internet. Firewall best practices and standard default firewall configurations can help protect against attacks that originate from the Internet. Microsoft has provided information about how you can help protect your PC. End users can visit the Protect Your PC Web site. IT professionals can visit the Security Guidance Center Web site.
What does the update do?
The update removes the vulnerability by modifying the way that MSDTC validates the length of a message before it passes the message to the allocated buffer.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure. Microsoft had not received any information to indicate that this vulnerability had been publicly disclosed when this security bulletin was originally issued.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers and had not seen any examples of proof of concept code published when this security bulletin was originally issued.
COM+ Vulnerability:
A remote code execution and local elevation of privilege vulnerability exists in COM+ that could allow an attacker who successfully exploited this vulnerability to take complete control of the affected system.
CVE Information:
CAN-2005-1978
Mitigating Factors for COM+ Vulnerability:
* On Windows XP Service Pack 2, on Windows Server 2003, and on Windows Server 2003 Service Pack 1 an attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability. The vulnerability could not be exploited remotely unless the attacker already has administrative permissions.
* Firewall best practices and standard default firewall configurations can help protect networks from attacks that originate outside the enterprise perimeter. Best practices recommend that systems that are connected to the Internet have a minimal number of ports exposed.
Workarounds for COM+ Vulnerability:
Microsoft has tested the following workarounds. While these workarounds will not correct the underlying vulnerability, they help block known attack vectors. When a workaround reduces functionality, it is identified in the following section.
* Disable COM+
Disabling COM+ helps protect the affected system from attempts to exploit this vulnerability. There are different ways to disable COM+, depending on which platform you are using.
Important This bulletin contains information about how to modify the registry. Make sure to back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs. For more information about how to back up, restore, and modify the registry, see Microsoft Knowledge Base Article 256986.
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
* On Windows 2000, create a file that is named ~clbcatq.dll in the %windir%\system32 folder. These steps create a similar environment as the issue that is discussed in Microsoft Knowledge Based Article 246499. To disable COM+ on Windows 2000, follow these steps:
1. Logon as an administrator.
2. Click Start, and then click Run and then type:
echo Workaround for KB902400 >%windir%\system32\~clbcatq.dll
3. Restart the system.
Note To re-enable COM+, delete the ~clbcatq.dll file and restart the system.
* To disable COM+ on Windows XP and Windows Server 2003, create a registry key and restart the computer to disable COM+:
On these operating system versions you can create a registry key and restart the machine to disable COM+.
1. Click Start, click Run, type "regedt32" (without the quotation marks), and then click OK.
2. In Registry Editor, locate the following registry key:
HKEY_LOCAL_MACHINE\Software\Microsoft\COM3
3. Double-click the COM+Enabled registry entry, and then change the value to 0.
Note Make a note of the current value so that you can reverse this procedure if required.
4. Quit Registry Editor and restart the system.
* Alternatively, you can paste the following text into a .reg file. Then, double-click the .reg file while you are logged on locally as an administrator:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\COM3]
"Com+Enabled"=dword:00000000
Note You can also apply this setting to multiple systems by using Group Policy. For more information about Group Policy, visit the following Microsoft Web Site.
Impact of Workaround: If you disable COM+, you cannot use any COM+ dependant applications. Customers should evaluate whether any business-critical applications rely on COM+ services before they deploy these workarounds. We recommend these workaround only on systems that cannot install the security update. For information about COM+, visit the following Microsoft Web site.
* Block the following at the firewall:
o UDP ports 135, 137, 138, and 445, and TCP ports 135, 139, 445, and 593
o If installed, COM Internet Services (CIS) or RPC over HTTP, which listen on ports 80 and 443
These ports are used to initiate a connection with RPC. Blocking them at the firewall will help protect systems that are behind that firewall from attempts to exploit this vulnerability. Also, make sure that you block any other specifically configured RPC port on the remote system. We recommend that you block all unsolicited inbound communication from the Internet to help prevent attacks that may use other ports. For more information about ports that RPC uses, visit the following Web site. For more information about how to disable CIS, see Microsoft Knowledge Base Article 825819.
Note Other protocols, such as Sequenced Packet Exchange (SPX) or NetBEUI, could be used to communicate with the MSDTC service. If you are using these protocols, you should block the appropriate ports for those protocols. For more information about IPX and SPX, visit the following Microsoft Web site.
* Disable DCOM
Disabling DCOM helps protect the affected system from remote attempts to exploit this vulnerability. However, the affected system could still be vulnerable to local elevation of privilege attacks that try to exploit this vulnerability. For instructions on how to disable DCOM, see Microsoft Knowledge Base Article 825750.
As an alternative to the steps that are documented In Microsoft Knowledge Base Article 825750, alternately you can paste the following text into a .reg file. Then, double-click the .reg file while you are logged on locally as an administrator:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Ole]
"EnableDCOM"="N"
Note You can also apply this setting to multiple systems by using Group Policy. For more information about Group Policy, visit the following Microsoft Web Site.
Impact of Workaround: If you disable DCOM, you cannot use any DCOM dependant applications. Customers should evaluate whether any business critical applications rely on DCOM services before you deploy this workaround. There are potentially many built-in components and third-party applications that are affected if you disable DCOM. We do not recommend that you disable DCOM in your environment until you have tested to discover what applications are affected. Disabling DCOM may not be possible in all environments. Therefore, we recommend this workaround only on systems that cannot install the security update. For information about disabling DCOM, see Microsoft Knowledge Base Article 825750.
FAQ for COM+ Vulnerability:
What is the scope of the vulnerability?
This is a remote code execution and local privilege elevation vulnerability. On Windows 2000 and Windows XP Service Pack 1, an anonymous attacker could remotely try to exploit this vulnerability. On Windows XP Service Pack 2, Windows Server 2003, and Windows Server 2003 Service Pack 1, this is strictly a local privilege elevation vulnerability because only an administrator can remotely access the affected component. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The process that COM+ uses to create and use memory structures.
What is COM+?
COM+ is the next step in the evolution of the Microsoft Component Object Model and Microsoft Transaction Server (MTS). COM+ handles resource management tasks, such as thread allocation and security. It automatically makes applications more scalable by providing thread pooling, object pooling, and just-in-time object activation. COM+ also helps protect the integrity of data by providing transaction support even if a transaction spans multiple databases over a network. For information about COM+, visit the following Microsoft Web site.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could take complete control of the affected system.
Who could exploit the vulnerability?
On Windows 2000 and Windows XP Service Pack 1, an anonymous attacker could try to exploit the vulnerability by creating a specially crafted network message and sending the message to an affected system. The message could then cause the affected system to execute code. On Windows XP Service Pack 2, Windows Server 2003 and Windows Server 2003 Service Pack 1, an attacker must be able to log on locally to a system to try to exploit the vulnerability. If an attacker logged on locally to a system, the attacker could then run a specially crafted application to gain administrative privileges to that system.
What systems are primarily at risk from the vulnerability?
Windows 2000 and Windows XP Service Pack 1 systems are primarily at risk from this vulnerability. The vulnerability could not be exploited remotely on Windows XP Service Pack 2, Windows Server 2003, and Windows Server 2003 Service Pack 1.
Could the vulnerability be exploited over the Internet?
Yes, by anonymous users on Windows 2000 and Windows XP Service Pack 1. Firewall best practices and standard default firewall configurations can help protect against attacks that originate from the Internet. Microsoft has provided information about how you can help protect your PC. End users can visit the Protect Your PC Web site. IT professionals can visit the Security Guidance Center Web site.
On Windows XP Service Pack 2, Windows Server 2003, and Windows Server 2003 Service Pack 1, an attacker must be able to log on to the specific system that is targeted for attack. An anonymous attacker cannot load and run a program remotely by using this vulnerability on these operating system versions.
What does the update do?
The update removes the vulnerability by modifying the way that COM+ creates and uses internal memory structures.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure. Microsoft had not received any information to indicate that this vulnerability had been publicly disclosed when this security bulletin was originally issued.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers and had not seen any examples of proof of concept code published when this security bulletin was originally issued.
TIP Vulnerability:
A denial of service vulnerability exists that could allow an attacker to send a specially crafted network message to an affected system. An attacker could cause the Distributed Transaction Coordinator to stop responding.
CVE Information:
CAN-2005-1979
Mitigating Factors for TIP Vulnerability:
* This is a denial of service vulnerability. This issue would not allow an attacker to execute code or to elevate their user rights, but it could cause the affected service to stop accepting requests.
* On Windows XP Service Pack 1, Windows XP Service Pack 2, Windows Server 2003, and Windows Server 2003 Service Pack 1, even if the Microsoft Distributed Transaction Coordinator is started, the TIP protocol is not enabled. An administrator must manually enable the TIP protocol for the Distributed Transaction Coordinator to become vulnerable to this issue.
* If the Microsoft Distributed Transaction Coordinator stops responding because of an attack, services that are not dependant on the Microsoft Distributed Transaction Coordinator would continue to function normally.
* For customers who require the affected component, firewall best practices and standard default firewall configurations can help protect networks from attacks that originate outside the enterprise perimeter. Best practices recommend that systems that are connected to the Internet have a minimal number of ports exposed.
Workarounds for TIP Vulnerability:
Microsoft has tested the following workarounds. While these workarounds will not correct the underlying vulnerability, they help block known attack vectors. When a workaround reduces functionality, it is identified in the following section.
* Disable the Distributed Transaction Coordinator
Disabling the Distributed Transaction Coordinator helps protect the affected system from attempts to exploit this vulnerability. To disable the Distributed Transaction Coordinator, follow these steps:
1. Click Start, and then click Control Panel. Alternatively, click Start, point to Settings, and then click Control Panel.
2. Double-click Administrative Tools.
3. Double-click Component Services.
4. Click Services.
5. Double-click Distributed Transaction Coordinator.
6. In the Startup type list, click Disabled.
7. Click Stop, and then click OK.
You can also stop and disable the Distributed Transaction Coordinator by using the following command at the command prompt:
sc stop MSDTC & sc config MSDTC start= disabled
Impact of Workaround: If you disable the Distributed Transaction Coordinator, you cannot use any service or application that is dependant on the Distributed Transaction Coordinator. This could include other applications such as SQL Server, BizTalk Server, Exchange Server, or Message Queuing. Also, this service is required in most clustering configurations. Therefore, we recommend this workaround only on systems that cannot install the security update.
* Use the Group Policy settings to disable the Distributed Transaction Coordinator on all affected systems that do not require this feature.
Because the Distributed Transaction Coordinator is a possible attack vector, disable it by using the Group Policy settings. You can disable the startup of this service at the local, site, domain, or organizational unit level by using Group Policy object functionality in Windows 2000 domain environments or in Windows Server 2003 domain environments. For more information about how to disable this service through logon scripts, see Microsoft Knowledge Base Article 297789
Note You may also review the Windows 2000 Security Hardening Guide. This guide includes information about how to disable services.
For more information about Group Policy, visit the following Web sites:
o Step-by-Step Guide to Understanding the Group Policy Feature Set
o Windows 2000 Group Policy
o Group Policy in Windows Server 2003
Impact of Workaround: If you disable the Distributed Transaction Coordinator, you cannot use any service or application that is dependant on the Distributed Transaction Coordinator. This could include other applications such as SQL Server, BizTalk Server, Exchange Server, or Message Queuing. Also, this service is required in most clustering configurations. Therefore, we recommend this workaround only on systems that cannot install the security update.
* Block TCP port 3372 at the firewall:
This port is used to initiate a connection with TIP. Blocking it at the firewall will help protect systems that are behind that firewall from attempts to exploit this vulnerability. Also, make sure that you block any other specifically configured TIP ports on the remote system. We recommend that you block all unsolicited inbound communication from the Internet to help prevent attacks that may use other ports.
* To help protect from network-based attempts to exploit this vulnerability, enable advanced TCP/IP filtering on systems that support this feature.
You can enable advanced TCP/IP filtering to block all unsolicited inbound traffic. For more information about how to configure TCP/IP filtering, see Microsoft Knowledge Base Article 309798.
* To help protect from network-based attempts to exploit this vulnerability, block the affected ports by using IPsec on the affected systems.
Use Internet Protocol security (IPsec) to help protect network communications. Detailed information about IPsec and about how to apply filters is available in Microsoft Knowledge Base Article 313190 and Microsoft Knowledge Base Article 813878.
FAQ for TIP Vulnerability:
What is the scope of the vulnerability?
A denial of service vulnerability exists that could allow an attacker to send a specially crafted network message to an affected system. An attacker could cause the Distributed Transaction Coordinator to stop responding. Note that the denial of service vulnerability would not allow an attacker to execute code or to elevate their user rights, but it could cause the affected system to stop accepting requests.
What causes the vulnerability?
The process that the Distributed Transaction Coordinator uses to validate TIP requests.
What is the Microsoft Distributed Transaction Coordinator?
The Microsoft Distributed Transaction Coordinator (MSDTC) is a distributed transaction facility for Microsoft Windows platforms. MSDTC uses proven transaction processing technology. It is robust despite system failures, process failures, and communication failures; it exploits loosely coupled systems to provide scalable performance; and it is easy to install, configure, and manage. The DTC service provides the following benefits:
* Reduces the cost of enterprise computing.
The DTC provides a sophisticated, low-cost distributed transaction facility for users of networked, commodity-priced PCs and servers.
* Simplifies application development.
DTC transactions greatly simplify the application task of preserving consistency, despite failures that can occur when updating application data.
* Provides a consistent transaction model.
The DTC supports a variety of resource managers, including relational databases, object-oriented databases, file systems, document storage systems, and message queues.
* Enables software development using distributed software components.
The DTC provides a simple, object-oriented application programming interface for initiating and controlling transactions.
For information about MSDTC, visit the following Microsoft Web site.
What is TIP?
MSDTC supports Transaction Internet Protocol (TIP). TIP transactions implicitly assume a two-pipe architecture. In this architecture, messages that describe the work flow on one pipe, the application-to-application pipe, and messages that control the transaction flow on another pipe, the transaction manager-to-transaction manager pipe. MS DTC selects TIP when an application program or resource manager explicitly uses the TIP COM interfaces. MS DTC also uses TIP when TIP is the only communication protocol that is common to both platforms. TIP is typically used when MS DTC is used in conjunction with transaction managers from other companies. For more information about TIP, visit the following Microsoft Web site. TIP is an IETF standard, documented at the following IETF Web site. For more information about security considerations that are associated with TIP, visit the following Microsoft Web site.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected service to stop responding.
Who could exploit the vulnerability?
When the TIP protocol is available, any anonymous user who could deliver a specially crafted network message to the affected system could try to exploit this vulnerability.
How could an attacker exploit the vulnerability?
An attacker could try to exploit the vulnerability by creating a specially crafted network message and sending the message to an affected system. The message could then cause the affected service to stop responding.
What systems are primarily at risk from the vulnerability?
Windows 2000 based versions of the Microsoft Distributed Transaction Coordinator are primarily at risk from this vulnerability because TIP is enabled by default. If TIP is manually enabled on other operating system versions, they would be equally vulnerable to this issue.
Could the vulnerability be exploited over the Internet?
Yes. An attacker could try to exploit this vulnerability over the Internet. Firewall best practices and standard default firewall configurations can help protect against attacks that originate from the Internet. Microsoft has provided information about how you can help protect your PC. End users can visit the Protect Your PC Web site. IT professionals can visit the Security Guidance Center Web site.
What does the update do?
The update removes the vulnerability by modifying the way that MSDTC validates TIP requests.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure. Microsoft had not received any information to indicate that this vulnerability had been publicly disclosed when this security bulletin was originally issued.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers and had not seen any examples of proof of concept code published when this security bulletin was originally issued.
Distributed TIP Vulnerability:
A denial of service vulnerability exists that could allow an attacker to send a specially crafted network message to an affected system. An attacker could cause the Microsoft Distributed Transaction Coordinator (MSDTC) to stop responding. This specially crafted message could also be transferred through the affected system to another TIP server. This distributed attack could cause the MSDTC on both systems to stop responding.
CVE Information:
CAN-2005-1980
Mitigating Factors for Distributed TIP Vulnerability:
* This is a denial of service vulnerability. This issue would not allow an attacker to execute code or to elevate their user rights, but it could cause the affected services to stop accepting requests.
* On Windows XP Service Pack 1, Windows XP Service Pack 2, Windows Server 2003, and Windows Server 2003 Service Pack 1, even if the Microsoft Distributed Transaction Coordinator is started, the TIP protocol is not enabled. An administrator must manually enable the TIP protocol for the Distributed Transaction Coordinator to become vulnerable to this issue.
* If the Microsoft Distributed Transaction Coordinator stops responding because of an attack, services that are not dependant on the Microsoft Distributed Transaction Coordinator would continue to function normally.
* For customers who require the affected component, firewall best practices and standard default firewall configurations can help protect networks from attacks that originate outside the enterprise perimeter. Best practices recommend that systems that are connected to the Internet have a minimal number of ports exposed.
Workarounds for Distributed TIP Vulnerability:
Microsoft has tested the following workarounds. While these workarounds will not correct the underlying vulnerability, they help block known attack vectors. When a workaround reduces functionality, it is identified in the following section.
* Disable the Distributed Transaction Coordinator
Disabling the Distributed Transaction Coordinator helps protect the affected system from attempts to exploit this vulnerability. To disable the Distributed Transaction Coordinator, follow these steps:
1. Click Start, and then click Control Panel. Alternatively, click Start, point to Settings, and then click Control Panel.
2. Double-click Administrative Tools.
3. Double-click Component Services.
4. Click Services.
5. Double-click Distributed Transaction Coordinator.
6. In the Startup type list, click Disabled.
7. Click Stop, and then click OK.
You can also stop and disable the Distributed Transaction Coordinator by using the following command at the command prompt:
sc stop MSDTC & sc config MSDTC start= disabled
Impact of Workaround: If you disable the Distributed Transaction Coordinator, you cannot use any service or application that is dependant on the Distributed Transaction Coordinator. This could include other applications such as SQL Server, BizTalk Server, Exchange Server, or Message Queuing. Also, this service is required in most clustering configurations. Therefore, we recommend this workaround only on systems that cannot install the security update.
* Use the Group Policy settings to disable the Distributed Transaction Coordinator on all affected systems that do not require this feature.
Because the Distributed Transaction Coordinator is a possible attack vector, disable it by using the Group Policy settings. You can disable the startup of this service at the local, site, domain, or organizational unit level by using Group Policy object functionality in Windows 2000 domain environments or in Windows Server 2003 domain environments. For more information about how to disable this service through logon scripts, see Microsoft Knowledge Base Article 297789
Note You may also review the Windows 2000 Security Hardening Guide. This guide includes information about how to disable services.
For more information about Group Policy, visit the following Web sites:
o Step-by-Step Guide to Understanding the Group Policy Feature Set
o Windows 2000 Group Policy
o Group Policy in Windows Server 2003
Impact of Workaround: If you disable the Distributed Transaction Coordinator, you cannot use any service or application that is dependant on the Distributed Transaction Coordinator. This could include other applications such as SQL Server, BizTalk Server, Exchange Server, or Message Queuing. Also, this service is required in most clustering configurations. Therefore, we recommend this workaround only on systems that cannot install the security update.
* Block TCP port 3372 at the firewall:
This port is used to initiate a connection with TIP. Blocking it at the firewall will help protect systems that are behind that firewall from attempts to exploit this vulnerability. Also, make sure that you block any other specifically configured TIP ports on the remote system. We recommend that you block all unsolicited inbound communication from the Internet to help prevent attacks that may use other ports.
* To help protect from network-based attempts to exploit this vulnerability, enable advanced TCP/IP filtering on systems that support this feature.
You can enable advanced TCP/IP filtering to block all unsolicited inbound traffic. For more information about how to configure TCP/IP filtering, see Microsoft Knowledge Base Article 309798.
* To help protect from network-based attempts to exploit this vulnerability, block the affected ports by using IPsec on the affected systems.
Use Internet Protocol security (IPsec) to help protect network communications. Detailed information about IPsec and about how to apply filters is available in Microsoft Knowledge Base Article 313190 and Microsoft Knowledge Base Article 813878.
FAQ for Distributed TIP Vulnerability:
What is the scope of the vulnerability?
A denial of service vulnerability exists that could allow an attacker to send a specially crafted network message to an affected system. An attacker could cause the Distributed Transaction Coordinator to stop responding. Note that the denial of service vulnerability would not allow an attacker to execute code or to elevate their user rights, but it could cause the affected system to stop accepting requests.
What causes the vulnerability?
The process that the Distributed Transaction Coordinator uses to validate TIP requests.
What is the Microsoft Distributed Transaction Coordinator?
The Microsoft Distributed Transaction Coordinator (MSDTC) is a distributed transaction facility for Microsoft Windows platforms. MSDTC uses proven transaction processing technology. It is robust despite system failures, process failures, and communication failures; it exploits loosely coupled systems to provide scalable performance; and it is easy to install, configure, and manage. The DTC service provides the following benefits:
* Reduces the cost of enterprise computing.
The DTC provides a sophisticated, low-cost distributed transaction facility for users of networked, commodity-priced PCs and servers.
* Simplifies application development.
DTC transactions greatly simplify the application task of preserving consistency, despite failures that can occur when updating application data.
* Provides a consistent transaction model.
The DTC supports a variety of resource managers, including relational databases, object-oriented databases, file systems, document storage systems, and message queues.
* Enables software development using distributed software components.
The DTC provides a simple, object-oriented application programming interface for initiating and controlling transactions.
For information about MSDTC, visit the following Microsoft Web site.
What is TIP?
MSDTC supports Transaction Internet Protocol (TIP). TIP transactions implicitly assume a two-pipe architecture. In this architecture, messages that describe the work flow on one pipe, the application-to-application pipe, and messages that control the transaction flow on another pipe, the transaction manager-to-transaction manager pipe. MS DTC selects TIP when an application program or resource manager explicitly uses the TIP COM interfaces. MS DTC also uses TIP when TIP is the only communication protocol that is common to both platforms. TIP is typically used when MS DTC is used in conjunction with transaction managers from other companies. For more information about TIP, visit the following Microsoft Web site. TIP is an IETF standard, documented at the following IETF Web site. For more information about security considerations that are associated with TIP, visit the following Microsoft Web site.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected service to stop responding.
Who could exploit the vulnerability?
When the TIP protocol is available, any anonymous user who could deliver a specially crafted network message to the affected system could try to exploit this vulnerability.
How could an attacker exploit the vulnerability?
An attacker could try to exploit the vulnerability by creating a specially crafted network message and sending the message to an affected system. The message could then cause the affected service to stop responding.
What systems are primarily at risk from the vulnerability?
Windows 2000 based versions of the Microsoft Distributed Transaction Coordinator are primarily at risk from this vulnerability because TIP is enabled by default. If TIP is manually enabled on other operating system versions, they would be equally vulnerable to this issue.
Could the vulnerability be exploited over the Internet?
Yes. An attacker could try to exploit this vulnerability over the Internet. Firewall best practices and standard default firewall configurations can help protect against attacks that originate from the Internet. Microsoft has provided information about how you can help protect your PC. End users can visit the Protect Your PC Web site. IT professionals can visit the Security Guidance Center Web site.
What does the update do?
The update removes the vulnerability by modifying the way that MSDTC validates TIP requests.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure. Microsoft had not received any information to indicate that this vulnerability had been publicly disclosed when this security bulletin was originally issued.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers and had not seen any examples of proof of concept code published when this security bulletin was originally issued.
|
| Subject:
|
Error after installation of KB902400 on some PCs with Windows 2000 Pro and XP Pro |
Date: |
30 Oct. 2005 |
| From: |
gmdgmdgmdabv.bg |
The following error appears in application logs after installation of this update: "The COM+ Event System detected a bad return code during its internal processing. HRESULT was 80070005 from line 44 of d:\qxp_slp\com\com1x\src\events\tier1\eventsystemobj.cpp ....."
It causes disappear of the icons in "network connections" and impossibility to log on of the users (except of admins), and may be more damages. Uninstalling of KB920400 restores the good condition of the affected PC`s.
This problem appears in some PC only.
Thanks in advance. |
|
| Subject:
|
Error after installation of KB902400 on some PCs with Windows 2000 Pro and XP Pro |
Date: |
7 Sep. 2007 |
| From: |
Sergio Graziosi |
Got the same problem, after lots of trials I've found out that the solution is:
http://support.microsoft.com/kb/909444
steps 1,2,3 for win2000 worked on my winXP SP2 box. |
|
|
|
|
|
|
