So I'm not clear...if someone clicks on "Help and Support" in 2003 / XP it's 
possible for them to get exploted because they might look for something and get 
redirected to a compromised site? I'm not clear...what would my users have to 
go to get exploited?
David Lum // SYSTEMS ENGINEER
NORTHWEST EVALUATION ASSOCIATION
(Desk) 971.222.1025 // (Cell) 503.267.9764

From: Ziots, Edward [mailto:[email protected]]
Sent: Thursday, June 10, 2010 6:46 AM
To: NT System Admin Issues
Subject: RE: More pain on the Windows front, possible 0 day

What I am thinking if we don't have the spot in the registry, then maybe 
configuring your web filtering, to block all URL's  or sequences that are 
calling HCP://

Per the seclist.org site the rogue html file had the following in it:
$ cat starthelp.html
<iframe src="hcp://...">

But this was shown accordingly;

Few users rely on Help Centre urls, it is safe to temporarily disable them

by removing HKCR\HCP\shell\open. This modification can be deployed easily using

GPOs. For more information on Group Policy, see Microsoft's Group Policy site,

here



This is the exported registry per my XP SP3 system.

Windows Registry Editor Version 5.00



[HKEY_CLASSES_ROOT\HCP]

@="Help Center Pluggable Protocol"

"URL Protocol"=""

"EditFlags"=dword:00000002

"FriendlyTypeName"="@C:\\WINDOWS\\PCHealth\\HelpCtr\\Binaries\\HCAppRes.dll,-2100"



[HKEY_CLASSES_ROOT\HCP\shell]



[HKEY_CLASSES_ROOT\HCP\shell\open]



[HKEY_CLASSES_ROOT\HCP\shell\open\command]

@="\"C:\\WINDOWS\\PCHealth\\HelpCtr\\Binaries\\HelpCtr.exe\" -FromHCP -url 
\"%1\""



Then you can send save this .reg file for restoration procedures if needed.



The following the directions in http://support.microsoft.com/kb/310516



Basically I believe it would look like the following for



HCPfix.reg



[-HKEY_CLASSES_ROOT\HCP]

@="Help Center Pluggable Protocol"

"URL Protocol"=""

"EditFlags"=dword:00000002

"FriendlyTypeName"="@C:\\WINDOWS\\PCHealth\\HelpCtr\\Binaries\\HCAppRes.dll,-2100"



[-HKEY_CLASSES_ROOT\HCP\shell]



[-HKEY_CLASSES_ROOT\HCP\shell\open]



[-HKEY_CLASSES_ROOT\HCP\shell\open\command]

@="\"C:\\WINDOWS\\PCHealth\\HelpCtr\\Binaries\\HelpCtr.exe\" -FromHCP -url 
\"%1\""



Then do a test deploy with Startup GPO with the following as the script.

HCPfix.cmd
regedit.exe /s HCPFIX.reg







http://technet.microsoft.com/en-us/windowsserver/bb310732.aspx


I haven't tried it, since I have HIPS at the workstation is a mitigation 
control, but for those who don't this might just be the workaround you are 
going to need before M$ puts out an OOB patch if they are going too.  Depends 
on how many PCs you have at risk, how much privileges your users have and how 
much of a threat you believe them to be at against this exploit from the 
internet.

Sincerely,
EZ

Edward Ziots
CISSP,MCSA,MCP+I,Security +,Network +,CCA
Network Engineer
Lifespan Organization
401-639-3505
[email protected]

From: James Rankin [mailto:[email protected]]
Sent: Thursday, June 10, 2010 9:14 AM
To: NT System Admin Issues
Subject: Re: More pain on the Windows front, possible 0 day

I think it is just for XP/2003, and it is the MS Help Center stuff

It actually doesn't work properly on 2008, as far as I can tell - I was looking 
a bit too deep
On 10 June 2010 14:08, David W. McSpadden 
<[email protected]<mailto:[email protected]>> wrote:
I don't have it as well but I am win7pro and I didn't install the HP help 
center software??
Maybe??


________________________________
From: James Rankin [mailto:[email protected]<mailto:[email protected]>]
Sent: Thursday, June 10, 2010 8:38 AM

To: NT System Admin Issues
Subject: Re: More pain on the Windows front, possible 0 day

I can't find the protocol handler anywhere in HKCR?
On 10 June 2010 13:31, Joe Tinney 
<[email protected]<mailto:[email protected]>> wrote:
The article Susan linked had a mitigations section. The one I am most 
interested in was the temporary disabling of the hcp protocol handler in the 
registry.

http://lock.cmpxchg8b.com/b10a58b75029f79b5f93f4add3ddf992/ADVISORY

From: Ziots, Edward [mailto:[email protected]<mailto:[email protected]>]
Sent: Thursday, June 10, 2010 7:23 AM

To: NT System Admin Issues
Subject: RE: More pain on the Windows front, possible 0 day

My intial thought would be HIPS to block the helpctr from even being called, 
either that or stopping the help and support center service, and ACLing the 
helpctr.exe. But still waiting to see what comes up on the Security lists from 
Microsoft that Susan Bradley myself and others are on, for additional 
mitigation aspects.

It is a unique exploit since it combines XSS with a hex obfuscation to bypass 
windows system controls.

Z

Edward Ziots
CISSP,MCSA,MCP+I,Security +,Network +,CCA
Network Engineer
Lifespan Organization
401-639-3505
[email protected]<mailto:[email protected]>

From: James Rankin [mailto:[email protected]<mailto:[email protected]>]
Sent: Thursday, June 10, 2010 7:16 AM
To: NT System Admin Issues
Subject: Re: More pain on the Windows front, possible 0 day

Saw this earlier on Patch Management...any word yet on workaround/mitigation to 
keep us sane until the inevitable OOB patch comes around?
On 10 June 2010 12:00, Ziots, Edward 
<[email protected]<mailto:[email protected]>> wrote:
http://www.theregister.co.uk/2010/06/10/windows_help_bug/
http://seclists.org/fulldisclosure/2010/Jun/205

Looks like a combination of XSS, and invoking the hcp protocol for help and 
support center to execute commands in the context of the logged on user.

PS: Mad Props to Susan Bradley on the Patch Management list for putting this 
out....

Z

Edward Ziots
CISSP,MCSA,MCP+I,Security +,Network +,CCA
Network Engineer
Lifespan Organization
401-639-3505
[email protected]<mailto:[email protected]>


~ Finally, powerful endpoint security that ISN'T a resource hog! ~
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"On two occasions...I have been asked, 'Pray, Mr Babbage, if you put into the 
machine wrong figures, will the right answers come out?' I am not able rightly 
to apprehend the kind of confusion of ideas that could provoke such a question."















--
"On two occasions...I have been asked, 'Pray, Mr Babbage, if you put into the 
machine wrong figures, will the right answers come out?' I am not able rightly 
to apprehend the kind of confusion of ideas that could provoke such a question."











--
"On two occasions...I have been asked, 'Pray, Mr Babbage, if you put into the 
machine wrong figures, will the right answers come out?' I am not able rightly 
to apprehend the kind of confusion of ideas that could provoke such a question."









~ Finally, powerful endpoint security that ISN'T a resource hog! ~
~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/>  ~

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