deactivating DCOM

B

Bijan Kianifard

Hello to all,

I recieve this message from eeye digital security and I
think it is interesting to you:


Microsoft Remote Procedure Call (RPC) Vulnerability

Systems Affected
All current versions of Microsoft Windows (e.g. Windows
NT, XP, 2000) and Windows Server 2003.

Potential Impact
This critical flaw allows an attacker to gain control of
systems via TCP Port 135. The flaw is not necessarily in
RPC, rather the flaw is in the way RPC is implemented in
Windows. When exploited, a buffer overflow is created that
could allow remote attackers to run commands with the
highest system privileges.

Rating: Critical
Many networked Windows services rely on RPC in order to
communicate between machines. As a result, Microsoft ships
Windows with this service turned on by default. This means
that every Windows machine is vulnerable, unless it has
been specifically set up to not use RPC (a configuration
which may cause parts of the operating system to function
incorrectly), or unless a patch or workaround has been
applied.

Protecting Against This Vulnerability
The most effective way to protect vulnerable systems is to
apply the Hotfix released by Microsoft in Security
Bulletin MS03-026. However, there is a workaround that
will disable the flawed Windows component so that an
attack over TCP Port 135 will be ineffective. According to
the Microsoft Security Bulletin, the affected service,
known as Distributed Component Object Model (DCOM), may be
disabled with little or no impact to normal Windows
functionality. The procedure for deactivating this
component consists of only a few steps, and is outlined in
the "Frequently Asked Questions" section of the Microsoft
bulletin.

DCOM has long been regarded as a potential security hazard
in Windows, and best security practices recommend
disabling the service unless it is absolutely necessary.
For this reason, Retina® Network Security Scanner has
included an audit for well over a year that flags Windows
machines on which the DCOM service is running. The fix
information included within the audit instructs users to
disable DCOM using the same procedure outlined by
Microsoft.



I don't know how can I deactivate DCOM service on windows
2000 advanced server platform,may somebody help me?

Thank you

Bijan
 
S

Susan Bradley, CPA aka Ebitz SBS Rocks [MVP]

Why not just patch the system?

But info is here.....
Port Authority, for Internet Port 135 :
http://nanoprobe.grc.com/port_135.htm


Bijan said:
Hello to all,

I recieve this message from eeye digital security and I
think it is interesting to you:

Microsoft Remote Procedure Call (RPC) Vulnerability

Systems Affected
All current versions of Microsoft Windows (e.g. Windows
NT, XP, 2000) and Windows Server 2003.

Potential Impact
This critical flaw allows an attacker to gain control of
systems via TCP Port 135. The flaw is not necessarily in
RPC, rather the flaw is in the way RPC is implemented in
Windows. When exploited, a buffer overflow is created that
could allow remote attackers to run commands with the
highest system privileges.

Rating: Critical
Many networked Windows services rely on RPC in order to
communicate between machines. As a result, Microsoft ships
Windows with this service turned on by default. This means
that every Windows machine is vulnerable, unless it has
been specifically set up to not use RPC (a configuration
which may cause parts of the operating system to function
incorrectly), or unless a patch or workaround has been
applied.

Protecting Against This Vulnerability
The most effective way to protect vulnerable systems is to
apply the Hotfix released by Microsoft in Security
Bulletin MS03-026. However, there is a workaround that
will disable the flawed Windows component so that an
attack over TCP Port 135 will be ineffective. According to
the Microsoft Security Bulletin, the affected service,
known as Distributed Component Object Model (DCOM), may be
disabled with little or no impact to normal Windows
functionality. The procedure for deactivating this
component consists of only a few steps, and is outlined in
the "Frequently Asked Questions" section of the Microsoft
bulletin.

DCOM has long been regarded as a potential security hazard
in Windows, and best security practices recommend
disabling the service unless it is absolutely necessary.
For this reason, Retina® Network Security Scanner has
included an audit for well over a year that flags Windows
machines on which the DCOM service is running. The fix
information included within the audit instructs users to
disable DCOM using the same procedure outlined by
Microsoft.

I don't know how can I deactivate DCOM service on windows
2000 advanced server platform,may somebody help me?

Thank you

Bijan

--
"Don't lose sight of security. Security is a state of being, not a
state of budget. He with the most firewalls still does not win.
Put down that honeypot and keep up to date on your patches. Demand
better security from vendors and hold them responsible. Use what
you have, and make sure you know how to use it properly and
effectively."
~ Rain Forest Puppy

http://www.wiretrip.net/rfp/txt/evolution.txt
 
S

Susan Bradley, CPA aka Ebitz SBS Rocks [MVP]

Q1 How do I enable or disable DCOM?

A. The HKEY_LOCAL_MACHINE\Software\Microsoft\OLE registry key has
"EnableDCOM" as a named value. By default this value is set to "Y." To
disable DCOM, change this value to "N." You can do this in the OLE/COM
Object Viewer with the File.System Configuration dialog box. Changing
this value requires you to restart your computer.

If EnableDCOM is not set to "Y," then all cross-computer calls are
rejected (the caller, typically, receives an RPC_S_SERVER_UNAVAILABLE
return code).

On Windows 95, with DCOM support, there is an additional registry
setting that enables or disables incoming remote connections. The
registry key is HKEY_LOCAL_MACHINE\Software\Microsoft\OLE, and the named
value is "EnableRemoteConnections." By default remote connections are
disabled (the value is "N"). To enable remote connections to a Windows
95 computer, change this value to "Y." You can do this in the OLE/COM
Object Viewer (OLEView) with the File.System Configuration dialog box.
Changing this value requires a restart.

You'll have to reboot anyway.... just in case they use another unknown
threat vector to get in, I'd rather patch. The exploit is not public at
this time....

Bijan said:
Hello to all,

I recieve this message from eeye digital security and I
think it is interesting to you:

Microsoft Remote Procedure Call (RPC) Vulnerability

Systems Affected
All current versions of Microsoft Windows (e.g. Windows
NT, XP, 2000) and Windows Server 2003.

Potential Impact
This critical flaw allows an attacker to gain control of
systems via TCP Port 135. The flaw is not necessarily in
RPC, rather the flaw is in the way RPC is implemented in
Windows. When exploited, a buffer overflow is created that
could allow remote attackers to run commands with the
highest system privileges.

Rating: Critical
Many networked Windows services rely on RPC in order to
communicate between machines. As a result, Microsoft ships
Windows with this service turned on by default. This means
that every Windows machine is vulnerable, unless it has
been specifically set up to not use RPC (a configuration
which may cause parts of the operating system to function
incorrectly), or unless a patch or workaround has been
applied.

Protecting Against This Vulnerability
The most effective way to protect vulnerable systems is to
apply the Hotfix released by Microsoft in Security
Bulletin MS03-026. However, there is a workaround that
will disable the flawed Windows component so that an
attack over TCP Port 135 will be ineffective. According to
the Microsoft Security Bulletin, the affected service,
known as Distributed Component Object Model (DCOM), may be
disabled with little or no impact to normal Windows
functionality. The procedure for deactivating this
component consists of only a few steps, and is outlined in
the "Frequently Asked Questions" section of the Microsoft
bulletin.

DCOM has long been regarded as a potential security hazard
in Windows, and best security practices recommend
disabling the service unless it is absolutely necessary.
For this reason, Retina® Network Security Scanner has
included an audit for well over a year that flags Windows
machines on which the DCOM service is running. The fix
information included within the audit instructs users to
disable DCOM using the same procedure outlined by
Microsoft.

I don't know how can I deactivate DCOM service on windows
2000 advanced server platform,may somebody help me?

Thank you

Bijan

--
"Don't lose sight of security. Security is a state of being, not a
state of budget. He with the most firewalls still does not win.
Put down that honeypot and keep up to date on your patches. Demand
better security from vendors and hold them responsible. Use what
you have, and make sure you know how to use it properly and
effectively."
~ Rain Forest Puppy

http://www.wiretrip.net/rfp/txt/evolution.txt
 

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