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Vista Hacking Challenge Answered

Posted by ScuttleMonkey on Mon Aug 07, 2006 06:11 PM
from the still-some-work-to-be-done dept.
debiansid writes "Microsoft's most secure Operating System yet has been compromised at the Black Hat hacker conference. We all know that Andrew Cushman, Microsoft's director of security outreach invited the Black Hats over to touch and feel Vista in order to showcase the superiority of this OS. Joanna Rutkowska, from Coseinc, a Singapore-based security firm, obliged and showed how it is possible to bypass security measures in Vista that prevents unsigned code from running with the help of a little software she calls the 'Blue Pill.'" To be fair, the hack was possible only when the target is in administrator mode rather than a limited user account.
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[+] IT: Microsoft Invites Black Hats into Vista 189 comments
gtzpower writes "Microsoft is inviting hackers to 'Take Your Best Shot' at Vista. 'You need to touch it, feel it,' Andrew Cushman, Microsoft's director of security outreach, said during a talk at the Black Hat computer-security conference. 'We're here to show our work.'" From the article: "A security team with oversight of every Microsoft product — from its Xbox video game console to its Word program for creating documents — has broad authority to block shipments until they pass security tests. The company also hosts two internal conferences a year so some of the world's top security experts can share the latest research on computer attacks." Essentially a tie-in with an article we discussed yesterday.
[+] Blue Pill Myth Debunked 128 comments
njyoder writes "As previously posted about, Joanna Rutkowska claimed to have discovered an allegedly undetectable vulnerability in Vista that takes advantage of AMD cpu's virtualization capabilities. a virtualization professional (Anthony Liguori of the Xen project) has now voiced his opinion to state this is bunkum. There are two parts two this — the ability to take over the machine and seamlessly drop the OS into a VM (which is very difficult, but possible) and the ability to have windows run in the VM undetectably (which is impossible). In fact, Rutkowska's prototype is VERY detectable. This is unfortunate mistake that people make when they jump to conclusions based on what is unfounded speculation and that includes the assumption that this would somehow be Vista specific, if it worked (noting that Vista doesn't run with administrator privileges by default)."
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  • by Alcimedes (398213) on Monday August 07 2006, @06:14PM (#15862422)
    So if you're a black hat and you've found a new, as yet undiscovered hole in Vista, would you really go running to MS to tell them all about it so they can patch it?

    Or would you keep it to yourself in hopes that the final release will still contain the hole so you can pwn millions of new adoptors?
    • by twofidyKidd (615722) on Monday August 07 2006, @06:19PM (#15862449)
      More interestingly, will MS actually patch it, even with complete knowledge of the hole? If it further delays Vista's release (because of potentially complex code organization, or other roadblock), they might not even bother until later.
      • by rifftide (679288) on Monday August 07 2006, @07:06PM (#15862761)
        Now this is really cynical - but they may have planned it this way. It looks like Vista may blow by even the latest (January 2007) deadline to resolve a raft of useability bugs, and this gives them the perfect cover to extend the ship date without looking totally inept. "We were ready to RTM at the end of 2006 but some late-breaking vulnerabilities were discovered, and we decided we couldn't take chances with the security of our customers' systems."

        This is not just a matter of losing face. If the Windows team blows the revised date by several months (say April or later) AND it ships what is considered to be a lackluster product, many people will start considering the Windows codebase as a sustaining mode project. They will assume that Microsoft is busy preparing a brand new code base (based on FreeBSD plus .NET and DirectX, let's say) to debut five years from now, and will work out a transition plan for Win32 apps. Windows will be a lame duck in the minds of both customers and MS engineers. Alternatives will be sought.

      • by Anonymous Coward on Monday August 07 2006, @08:00PM (#15863002)
        They won't patch it because they can't. The software is really quite clever--it uses the hardware-based virtualization capabilities in newer AMD processors to move the currently running operating system into a VM (on the fly--no reboot!). Everything looks the same to the OS (no intermediary drivers like with VMWare, Virtual PC, et. al.)

        The software doesn't rely on a vulnerability in the OS, but rather a feature of the hardware... it could be ported to Linux/BSD/whatever quite easily.
    • by pedantic bore (740196) on Monday August 07 2006, @06:19PM (#15862450)
      I'd try to trick them in to rewriting some crucial piece of the security infrastructure at the last possible minute. That way, I'd never run out of new holes to fine.

      Perhaps I'd do this by smiling and saying that the OS was so secure that I couldn't find anything wrong with it and recommending, no, begging that they ship it in exactly its current form.

    • If you're a truely vile blackhat, you'd probably go for choice #2.

      Most of these people at the blackhat con aren't of ill intent, though. They're just hackers who won't let microsofts convenience get in the way of their fun.

      Besides, with Microsofts history, I'd say it's pretty unlikely this hole will be patched if vista comes out before 2008. They certainly didn't patch any other verison of windows with that kind of speed.
    • by jd (1658) <imipak@y3.14ahoo.com minus pi> on Monday August 07 2006, @11:37PM (#15863865) Homepage Journal
      No, the Black Hat wouldn't tell them about the hole. Well, not per-se. Not if there was some way of tricking Microsoft into thinking it was fixed, whilst leaving the Black Hat a back-door into everybody's systems. One way to do this would be to try and persuade Microsoft that only a subset of the values that would break security are a problem. Social engineer both the fix and the buglist. That way, if the Black Hat is ever detected, there's a good chance Microsoft will deem it a fixed bug and blame the victim, rather than investigating further.


      One of the dangers in hiring or consulting Black Hats who are any good is that 99% of security is all about social engineering - both the defence and the offense. Because of this, it is utterly impossible to distinguish between someone actually securing your systems and merely persuading you they have done so. Grey Hats will have basically the same social engineering skills but are more likely to teach you what to avoid, than to use those skills against you. This is not to say that Black Hats will always work against you - that's bad for business. All you can say is that what makes someone a Black Hat as opposed to a Grey Hat is that they wouldn't be opposed to doing so, and you'll never know.


      Oh yeah - I mentioned the use of social engineering in the protection of a system. The defences in any system will always be breakable with enough time and effort, so the only truly secure system is one that can socially engineer the attacker into believing that they have either already succeeded long before they really have or that there's nothing alive and listening for them to attack. Under no circumstances should obscurity be used as a substitute for social engineering. Obscurity hides what is important except to an attacker who has figured the obscurity out - which means that it can be used against the defender far more effectively than against the attacker. Social engineering hides nothing, it merely helps someone to see what they want to see. Because it hides nothing, it cannot be used against you, the worst possible case is that it'll cease to be as effective.

  • by mcguiver (898268) on Monday August 07 2006, @06:14PM (#15862423)
    show me the average home user who doesn't runs XP as administrator. Do they think that anything is going to change for Vista?
    • by twofidyKidd (615722) on Monday August 07 2006, @06:16PM (#15862440)
      I posted a similar comment mere seconds after yours. Bet I win with the most "redundant" down mods.
    • by DrDitto (962751) on Monday August 07 2006, @06:17PM (#15862442)
      show me the average home user who doesn't runs XP as administrator. Do they think that anything is going to change for Vista?

      Yes, it is going to change for Vista. The default user will not have admin privileges.
      • But they'll change that as soon as they need to install some drivers etc.
        • Vista's security scheme works like sudo or the OS X admin password dialog. You're out of your element.
            • Re:MS Support calls (Score:5, Informative)

              by SEMW (967629) on Monday August 07 2006, @06:42PM (#15862606)
              By default, the true administrator account is hidden and disabled by default. Most people won't even know it's there, and you have to go through a rigmarole to enable it if you really want it (these a how-to guide at http://www.computerworld.com/action/article.do?com [computerworld.com] [computerworld.com] mand=viewArticleBasic&articleId=9001970). The "administrator" account that Vista creates by default is actually a standard user that can temporarily elevate to admin privelages on a task-by-task basis. It pops up a dialogue box like http://www.winsupersite.com/images/showcase/winvis ta_ff_uac_13.jpg [winsupersite.com], letting you press a big button that says 'allow' if you know it's something you initiated (e.g. you're trying to install something). You don't need to logout and relogin.
            • Re:MS Support calls (Score:5, Informative)

              by ChronoReverse (858838) on Monday August 07 2006, @06:44PM (#15862616)
              This is the way it works:

              You can either be a limited user or an "administrator". By default in the current beta you're an "administrator".

              What this means is that everytime an action is undertaken that actually requires administrative rights, Vista will pop up a dialogue (a la security warnings in Internet Explorer) and make sure you really wanted to do that. If you think this would be annoying (and would just train users to click yes) let me tell you that it was actually worse in Beta1.

              There it popped up ALL the time and even if a background task does something that requires it, the entire system would stop and pop up the dialogue. At least now it'll just block and wait for you to notice the new task button and deal with it.

              If you're on a limited account, you'll have to run whatever it was you were trying to run with the context menu "Run as admin" item. Then you'll have to type the admin password. Then when the program does something that actually requires the rights, it may or may not pop up the UAC dialogue.


              At least MS is putting hoops for us to jump through.
        • by Reverend528 (585549) on Monday August 07 2006, @06:30PM (#15862527) Homepage
          But they'll change that as soon as they need to install some drivers etc.

          Short term administrator usage to install a driver isn't that big of a threat. The real problem will be legacy applications that won't run without administrator priviledges. That's what keeps most people from running everything as a user.

          • by tcc3 (958644) on Monday August 07 2006, @06:52PM (#15862666)
            Legacy apps my ass. I've seen plenty of new, professional grade software that is hamstrung by user level permissions. Sometimes Power User wont even satisy. Sloppy development is a big problem.

            You shouldnt be allowed to say "NT/2k/Xp compatible" if your software cant correctly handle user permissions.
      • I've been using the Beta for a while now and what this low priveleged account amounts to is a dialog popping up when elevated privaleges are required and asking "Do you want to continue?". My understanding is you can now call CreateProcess such that it will load this dialog if elevated privaleges are needed.

        Yes it's a great way to alert a knowledgable user that some background process may be playing where it doesn't belong but I still see thousands of end users blindly clicking "Continue" as with the old Ac
      • All Microsoft would have to do to prevent home users from runiing as Admin would be to put a check in MS Office and IE to make both of them fail to run on any admn account or possable put up a big ugly dialog box "You ar running as admin, Continue?, Are you sure? Really continue?" If these came up every 5 minutes people would not run as Admin but could still swtich over now and then. One other Idea would be to make the admin account aauto logout after 10 minutes. Lot of things they could have done.
        • Spend more time and work to make the OS intentionally and pointlessly annoy the user? No.

          If you wanted to take this approach, all you'd need to do is make it a bit scary. Hide the Admin account away, and maybe do something like Safe Mode, putting "Administrative Mode" in big ugly systemtype in the four corners of the screen. That, and make it so people rarely need to run in Admin mode.
        • All Microsoft would have to do to prevent home users from runiing as Admin would be to put a check in MS Office and IE to make both of them fail to run on any admn account or possable put up a big ugly dialog box "You ar running as admin, Continue?, Are you sure? Really continue?"

          That approach has been taken by some minor software projects - by preventing use of the root account. This takes the wrong approach to security - it enocurages lax code under the false assumption that it couldn't possibly inflict

    • Yes, it WILL change if microsoft stops assuming that everyone can act as a full administrator, which they're going to do based on the latest beta.

      http://www.anandtech.com/systems/showdoc.aspx?i=27 80&p=7 [anandtech.com]

      The above article details a new "User Account Control" system. From TFA: "The basic premise behind UAC is that the previous way of running everything as an Administrator was wrong, and by doing so it not only allowed applications to make system-wide changes when they shouldn't, but it also meant that com
        • Perhaps the computer just shouldn't turn on.

          There's a point where you have to blame people for their own actions. That's roughly at the point where they start making explicit choices based on available information. Anything more, and the OS (or any other program) just starts becoming useless under the weight of handholding and artificial restrictions.

          About the only thing I could see worth adding (if it isn't already... I haven't kept up on the Vista betas) is some sort of good central logging function, so w
  • by twofidyKidd (615722) on Monday August 07 2006, @06:14PM (#15862427)
    Unfortunately, I think it's been established that many "average" users run in that mode, regardless of security concerns. I wonder if Vista will be an exception to this.
    • by TWX (665546) on Monday August 07 2006, @06:29PM (#15862524)
      That's because they have to run as a member of the Administrators group in order to do fairly mundane tasks like install software or make use of otherwise-mundane consumer hardware.

      I've had accounts on POSIX-compliant systems for years. I've found that with only user-level access I'm quite able to compile or install applications for my own user account in my own home directory without much difficulty, and still maintain the system integrity. As long as Microsoft holds on to the registry they'll never achieve such.
      • That's because they have to run as a member of the Administrators group in order to do fairly mundane tasks like install software or make use of otherwise-mundane consumer hardware.

        Bingo.

        I've tried, I've tried so hard to get my family to run using user-level accounts. It doesn't work. I don't live with them, so at least one needs an account with Admin rights. The others get the password (usually by asking), and then reelevate themselves. They aren't doing it to spite me. When some games won't run without admin, they can't burn CDs, so forth, they will find a way to make it work. Security? What's that? They don't care. If they can't play games, or burn CDs, they don't care about security.

        I know it is nice and easy to blame developers. True, they should do better. Heck, the first two release versions of my software didn't run properly as a user under Windows either (be gentle, I didn't have XP then). But if you want developers to behave, it has to cost them if they don't. The admin-by-default situation in Windows is ludicrous. They took a step in the right direction with user accounts in XP, but with the default installation forcing the first user account to be admin, and then not letting you de-admin the account, makes the step almost pointless.

        When default users run as an ordinary user with a pretty graphical sudo, and the OS blocks running apps as administrator without some sort of painful confirmation process (eg. whitelist), and developers have access to decent commandline or API sudo and security equivalents, then developers will behave and make damn sure their app runs as an ordinary user.

        Legacy apps will break unless some sort of layer is put in to make it look like the app does have arbitrary permissions to do fun stuff like write into its installation directory or the top level of a drive. I've heard Vista does some of this funky stuff (I'd check if the a__holes at Microsoft actually let me get their beta version of Vista- another story), which I hope is true.

        Microsoft got themselves into this mess and they have nobody to blame but themselves (despite the way they love to blame third parties for their sloppy OS). They can dig their way out if they choose. It won't be easy, but give them a decade and they'll be where Unix was a decade ago. ;) Perhaps Vista will be another step in the right direction. Or maybe it will be another case of dialog overkill that does nothing for true security. Who knows?

        Personally I'm not too stressed one way or the other. I don't use Windows unless I absolutely must, and whilst it is a worm-ridden crash-prone security nightmare it does mean there will be work available to clean up the mess. The target market of my software mostly runs on Windows though, so I do have to keep aware of what is going on. It would be nice if they cleaned up their act, as it makes my work easier.
  • Hypocrites (Score:3, Insightful)

    by Umbral Blot (737704) on Monday August 07 2006, @06:18PM (#15862447) Homepage
    Lets see how long it takes for slashdot readers to swing into full hypocrisy mode. Specifically mocking windows because it is vulnerable to users running insecure software in administrator mode when every other OS has the exact same vulnerability. Of course windows users do have the unfortunate tendency to run as administrators, but 1- that is blaming the software for the problems of the user, and 2- Vista might be running in user mode by default.

    And no, before you ask, I am not a windows user, I am on a Mac PowerBook G4. I prefer the mac because it is easier to use and I am not a gamer, not because of some imagined speed or innate security edge over every possible windows product.
    • Re:Hypocrites (Score:4, Insightful)

      by swissmonkey (535779) on Monday August 07 2006, @06:23PM (#15862477) Homepage
      Even better, not only has the tool to run in administrator mode to work, but additionally, the user has to click "Yes" in a dialog box warning him that this program is touching sensitive parts of the system(that's the UAC part).

      Now if that's a security issue, then I guess rm -rf / is an enormous security hole on Unix systems
  • by Anonymous Coward on Monday August 07 2006, @06:18PM (#15862448)
    ...but the user has to PERMIT the program to run.

    Yes, many users are just stupid and will automatically click "yes" on things, but at that point it's their own damn fault. The hack won't work without the user letting it work.
  • To be fair to MS (Score:5, Insightful)

    by walnutmon (988223) on Monday August 07 2006, @06:22PM (#15862474)
    This article is a little slanted towards, "MS said you can't get into their OP, and black hats said, 'bitch please!'". But really, MS probably expected this, and was hoping that they could learn something from watching a collection of hackers test their system. The more problems that are caught now, the less when it is released.

    Microsoft doesn't care about impressing Linux users, they care about releasing something that A LOT of normal users can install and forget about. Every iteration they get more stuff right, and their operating system becomes better (except ME, that sucked dick).
    • by Anonymous Coward on Monday August 07 2006, @10:57PM (#15863706)
      except ME, that sucked dick.

      once again, we're reminded of the importance of proper comma placement.
  • by rufusdufus (450462) on Monday August 07 2006, @06:23PM (#15862479)
    She also admitted that she had to perform the hack in higher privileged administrator mode rather than the lower privileged user account control.

    Seems to me this 'hack' gets the cart before the horse. If you are able to run malicious software in administrator mode, you can do anything at all, not just compromise signed code authorization. Heck you could replace the whole OS. The point of security is to prevent unknown persons from being able to run malicious software in the first place.

        • Sure if you have access to this "general purpose hardware" you can boot it off a cd or whatever to get around security checks, but that's not what this is about. This is about Vista supposedly not allowing you to load unsigned code into ring0, which is TOTALLY possible on general purpose hardware, because of a little thing called "protected mode", which allowes software in ring0 to control things that software in the lower rings does, by catching any attempts to directly access hardware or memory, and eithe
  • question (Score:5, Interesting)

    by spykemail (983593) on Monday August 07 2006, @06:26PM (#15862503) Homepage
    The real question is: will elevating oneself to administrator become common practice or not? If admin land stay reserved for the likes of Slashdot, then problems like this will probably be greatly reduced. But that assumes that the difficulty in setting up an admin account isn't worth it for most people.
  • Blue Pill (Score:3, Funny)

    by frosty_tsm (933163) on Monday August 07 2006, @06:29PM (#15862523)
    Nooo, take the Red Pill!
  • Hardware bug (Score:3, Informative)

    by diegocgteleline.es (653730) on Monday August 07 2006, @06:31PM (#15862531)
    This "trick" uses a hardware bug, not a sofware bug, to exploit Vista. It should affect other OSes like Linux, Solaris, BSDs, etc.

    I'm not surprised that they focused on being able to break Vista. A nice marketing move for the "researcher" (like there're not papers that explain how virtualizing environments aren't 100% safe in the x86 architecture)
  • by SafariShane (560870) on Monday August 07 2006, @06:38PM (#15862587)
    From the article...

    Reportedly, Vista is the first Microsoft products [sic] that the company is sending through its "Security Development Lifecycle", which aims at getting rid of all security vulnerabilities before shipping.

    Begs the question(s)...

    1. Why didn't microsoft try to get rid of all security vulnerabilities in other releases prior to shipping?

    2. Who at microsoft would even claim such a thing?

    Most security experts understand that 'security' is an arms race. I for one would rather measure the security of an os by the mean time between discovery and patch implementation. Microsoft is half right, they have the most vunerabilities because they are the dominant os, thus the biggest target. (yes, I know it's easier to hack ms, but that's not my point here) Even if Vista is far more secure and much harder to hack, if it has the largest install base it will have the most vunerabilities.

    I take issue with this part of the artice...

    She also admitted that she had to perform the hack in higher privileged administrator mode rather than the lower privileged user account control.

    Since when did that make any bit of difference? Hackers have been using social engineering tricks since they were called phreakers. And most people forget that it's purely a numbers game. They don't expect every end user to fall for an email titled "i love you" or "free pron". But, a small percentage will take the blue pill, and some of them will even switch to admin mode when the cute little screen saver they won for being the 500,000th visitor to some domain misspelling.

    Getting rid of ALL venerabilities? Ha, not even cutting the network cable could do that. There is always sneakernet. I for one want to run a system where zero day vunerabilites are just that, around for zero days.
  • by Poromenos1 (830658) on Monday August 07 2006, @06:39PM (#15862591) Homepage
    This contest doesn't make sense, if they find a vulnerability, it's some bad PR, but, well, how many vulnerabilities have been found and patched for XP? If they don't, it still doesn't mean it's unhackable, it just means they need more time.

    The only case where they DO work is when you're asking people to crack encryption, and then it's only CRACKING it that proves something, saying that noone could crack it doesn't mean it's uncrackable.
  • freeware? (Score:3, Interesting)

    by colmore (56499) on Monday August 07 2006, @06:52PM (#15862667) Journal
    So does this mean I'm going to need to be in administrator mode to run free software?

    Since just about everyone runs one or two pieces of free software (Windows isn't capable of very much out of the box) doesn't this mean that *everyone* will still be running in administrator mode?
  • by etresoft (698962) on Monday August 07 2006, @07:18PM (#15862825)
    People hack a MacBook using 3rd party hardware and software that they won't reveal, then claim the hack would also work on hardware they didn't demonstrate, then claim Apple "leaned on them" to keep the details secret. Suddenly, Macs have no more security. TFA didn't go into enough detail about the "Blue Pill". It wasn't really a hack in the same sense. It was a proof-of-concept to insert a rootkit into an x64-based OS without hacking. To quote the original author [blogspot.com],
    I would like to make it clear, that the Blue Pill technology does not rely on any bug of the underlying operating system. I have implemented a working prototype for Vista x64, but I see no reasons why it should not be possible to port it to other operating systems, like Linux or BSD which can be run on x64 platform.
    People aren't worried about how to hack into Vista, they are working on brand new exploitation architectures using Vista. I have read elsewhere where Vista appears to have a TCP/IP stack designed from scratch. It includes all new implementations of the bugs that have been fixed over the past 15 years in all the other OSes.
  • by Myria (562655) on Tuesday August 08 2006, @12:20AM (#15863999)
    This is about x64 driver signing. In Vista 64, drivers *cannot* run if they are not signed by a corporation who has paid the "VeriSign Tax" *. Even if the administrator requests it, they will not run. This is retarded "security", and it will keep being broken until Microsoft either gives up or forces everyone to have TPM bootup (more likely the latter).

    It infuriates developers, yet doesn't do anything for preventing rootkits, as Joanna has demonstrated. As long as user-mode programs have raw disk access, they will be able to attack whatever they want.

    I have a feeling that Microsoft's response to this will be to lock out raw disk access to user mode regardless of privilege. Keep in mind that even SELinux does not do this. All disk utilities would have to be written as signed drivers. The problem here is that developers won't stand for it, and will make signed drivers that grant access again. Then the rootkits can just copy these signed drivers then use them to do the same thing.

    Even if Microsoft encrypts the page file or removes the ability for the kernel to page itself out, raw disk access is still an issue. You can always open \Device\Harddisk0\Partition0 (NT's /dev/hda) and overwrite the MBR, then call NtShutdownSystem to reboot. If you take away raw disk access to user mode, then you get more esoteric. Detect when a blank CD or DVD has been inserted. When the user requests to burn it, intercept the write request and burn something else instead. Act like a system crash and reboot after it's done. Most computers are configured by default to boot from CD first.

    The real reason for driver signing appears to be DRM. The easiest way to "crack" song DRM is to install a fake audio driver that logs to disk. With the DMCA, it's illegal to make such a driver, and with driver signing, it's impossible to do it anonymously. If you temporarily disable driver signing - which is possible if you press F8 each boot - Vista's Windows Media Player refuses to play protected songs. Gee I wonder why.

    By the way, I thought of the same pagefile hack as Joanna on my own and posted it on my weblog in early June. I'm sure Joanna figured it out long before me though.

    * There are other root certificate companies that are countersigned, but this is a well-known phrase.

    Melissa
    • "How is this any different from sitting down at a Linux system with root access and running amok?"

      Because linux (without something like selinux) isn't designed to not let you run unsigned code in ring0. Vista is. Yet by using this security hole, you can push unsigned code into ring0. Therefore, it is only as secure as linux; their extra security requiring cryptographically signed binaries to run in ring0 didn't work.

      • You know, 100 years ago the automobile had a lot of problems too. Let's call all modern cars crap because the transmission still goes bad despite the fact that it goes bad 100,000 miles later than it did initially.

        Are you seriously reading what you're writing? Sorry, but 90% of corporate America does not nor even needs to run as admin. For those that do, think home PCs they have the runas option which is just like sudo so what's the problem? Maybe because all those lazy developers made programs for Window

    • The "idea" (I don't know how far vista goes towards this) is that you have a 'trusted' ring, where everything yes, does have to be signed. You may still have an unstrusted ring, for running unsigned code, but it will not be able to access anything protected within the trusted ring.

      It's basically like two seperate sandboxes, both kept seperate, and one of them highly controlled so you can trust (as much as you trust the key issuer) that it's safe and secure. The other... use at your own risk.