No sure how this will effect anyone but here you go....

Windows XP SP2 is big step forward in security--but it can break things

June 7, 2004
John McCormick

Takeaway:
Learn about the plethora of security enhancements that Microsoft has
included in windows XP Service Pack 2, as well as how these security
features could impair the functionality of some applications.

The release of Service Pack 2 for Windows XP will mark a milestone in the
life of this operating system. Microsoft is pulling out all the stops to
improve security. So much so, in fact, that it will cause many
problems-because SP2 will de-emphasize backward compatibility with legacy
systems and code for the sake of security. Administrators need to know in
advance just what SP2 will mean for the Windows XP systems on their
networks.

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Based on Service Pack 2 RC1
The information in this article is based on Windows XP Service Pack 2,
Release Candidate 1. There could be a few minor changes to the software in
the final release, but nearly everything you read here will still apply.


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Details
Windows XP SP2 will dramatically improve the default security configuration
for XP in nearly every area from e-mail to Web browsing to increased
protection against the ubiquitous buffer overrun. But, all of these security
improvements won't come without some considerable pain. ZDNetUK reports that
Microsoft admits that as many as one application in 10 will experience
problems due to the upgrade (I consider that a conservative estimate).

Here are some of the most important security changes that are part of XP
SP2:

The Internet Connection Firewall is now enabled by default, which should
improve security for SOHO users. However, in a corporate environment it
could cause problems for users trying to connect to network resources. The
firewall will also now activate much earlier in the boot cycle, even before
the network stack is enabled. On shutdown, it will now remain active until
after the stack is disabled.
The Messenger service is now disabled by default.
A pop-up ad blocker has been turned on by default.
A unified security application called the Windows Security Center has been
added (for more information on this feature, see this News.com article). It
is supposed to bring all of the most basic security configuration
information into one easy-to-manage place that will show whether your
firewall is enabled, if your antivirus software is working, and if you have
the latest software updates installed.
NX support is added to Windows XP. NX (no execute) will allow NX-enabled
CPUs to mark certain areas of memory as non-executable; that is, any code
pushed into those areas (perhaps by malware such as Blaster or other
viruses) will just sit there, unable to run and therefore will be rendered
harmless. This will harden the OS against the notorious buffer overrun
threats. NX is currently only supported for AMD's K8 and Intel's Itanium
processors, but 32- and 64-bit support for this important security feature
is expected in most future processor releases.
DCOM (the Distributed Component Object Model) gets a new set of restrictions
in the form of an access control list for nearly every action of any COM
server. There will also be a more detailed set of COM permissions, which
will allow administrators to fine-tune COM permission policies.
There is improved port management. It will no longer be up to the
application to close ports after it is finished. Before, if a developer left
out the closing routine or the application crashed, a port could remain open
and leave XP open to attack. SP2 encourages port management with an
application white list that only a user with administrator privileges can
alter. Placing an application (such as a peer-to-peer program) on the white
list causes ports to be managed automatically. Such applications can also
now be run as a regular user rather than needing local administrator
privileges to open ports in ICF.
New RPC restrictions help tighten communications. The XP SP2 changes in this
area let administrators fine-tune RPC services. This granular control over
RPC will allow you to specify that a port be used for RPC even if the
application is not on the white list. There are a lot of changes for RPC,
including a new RestrictRemoteClients registry key that by default blocks
most, but not all, remote anonymous access to RPC interfaces on the system.
The RPC interface restriction will require an RPC caller to perform
authentication, which makes it much more difficult to attack an interface,
and helps mitigate against Trojan attacks.
Potential problems
The NX protection mentioned above is an excellent example of something that
is definitely a powerful improvement from the security standpoint. However,
NX has already been reported to have caused considerable problems (at least
in the 64-bit version). The biggest problem will come for applications that
use just-in-time code creation. On the other hand, the .NET Framework common
language runtime code already supports NX as implemented in SP2.

RPC changes are the most likely to wreak havoc with existing applications.
In the pre-SP2 Windows XP implementation, there are literally scores of
RPC-based services running, all of which provide a window for attack. That
changes dramatically with SP2.

Because of the change in port management, if an application needs to open
ports but doesn't use stateful filtering, administrators installing it need
to place the program on the white list. With the built-in firewall enabled
by default, IPv4-application inbound connections for audio and video, such
as for MSN or Windows Messenger, need to have their port opening and closing
managed automatically. Inbound services connections (IPv4) will require some
changes to configuration and/or code. Services that listen on fixed ports
should ask users if the service should be permitted to open the port in ICF
and, if so, the service should use the INetFwV4OpenPort API to alter ICF
rules.

Another problem is the fact that Microsoft won't be offering this service
patch to those who hold pirated copies of Windows XP, which is reasonable
enough, but there are a lot of illegal copies out there, especially in the
Far East where a lot of worms get a quick foothold in the Internet. SP2 will
apparently check Product IDs looking for known pirated copies and will not
install on systems with bad Product IDs. This is understandable, but will
reduce the overall effectiveness of the security upgrade.

A lot of the potential problems posed by SP2 are beyond the control of
administrators. Some programming code for custom applications will have to
be rewritten, but at least now you know what to look for when problems come
up, rather than deploying XP SP2 and finding out that it breaks your most
important line-of-business application.


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Further reading
This report can only scratch the surface of such a major overhaul to an
operating system. For more information see:

XP SP2 Preview
XP SP2 RC1 Fact Sheet
XP SP2 RC1 Release Notes
XP SP2 Developer Notes

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Final word
I expect to hear screams of pain as people deploy SP2 and discover that
legacy applications no longer work, but those are probably the same people
who complain so loudly (and legitimately) that Microsoft doesn't deploy
secure systems.

Nearly every security expert knew that, at some point, Microsoft would be
forced to bite the bullet and take a big compatibility hit in order to
solidify operating system soft spots-many of which are due to legacy code
support. Plus, the XP SP2 changes will force developers to produce more
secure applications and not just take advantage of a permissive Windows OS
to write code that doesn't pay attention to security.

Of course, I would never recommend that anyone deploy such a major upgrade
widely the day it hits the street. You should install SP2 on a testing
network (or at least a single testing system) as soon as possible, and begin
compatibility testing for your specific applications.

Those of you who have the budgetary luxury of being able to conduct even
more extensive testing and want to get a leg up on evaluating XP SP2 even
before final release should check out the Technical Preview Program, which
makes SP2 RC1 generally available for testing by IT professionals (not just
those on the beta list). The initial download, which doesn't include any
support other than some Microsoft-sponsored newsgroups, requires Windows XP
to be installed already. English and German versions of the update are now
available and are about 270 MB in size.

As soon as you feel comfortable that Windows XP SP2 will not cause a
significant interruption for users (or you have fixed the issues that would
lead to a potential interruption), then you should deploy SP2 company-wide.
It is an important upgrade that can only improve the security of your
network.


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