Apple's Gatekeeper Still Broken (csoonline.com)

itwbennett writes: This weekend, Apple security expert Patrick Wardle will detail a vulnerability in Apple's Gatekeeper that makes it possible to bypass the anti-malware defense. This is the same vulnerability that was disclosed last April, which Apple said it patched later. Wardle was able to easily bypass Apple's fixes. He says "all Apple did was blacklist the signed apps he was abusing, but didn't fix the underlying issue, which is that, essentially, Gatekeeper functions as a guard that doesn't check" software already on the whitelist.

Comments

Doesn't matter.

[Anonymous Coward]

People will still flock to Apple and buy the shit out of it. And Apple knows it.

Re:Doesn't matter.

[Anonymous Coward]

Never let it be said that ignorance isn't bliss. You must be extremely happy.

Re:Doesn't matter.

[cant_get_a_good_nick]

I really never understood the anger of someone mad that someone else bought, well any item.

"you're such a _____ fanboi and you buy _____ and you suck (____'s CEO)'s dick!"

Who the hell cares. You buy what you want to buy, If you don't have a mac this doesn't affect you in the least. At least the Linux fanboi's could bitch at MS worms taking enough bandwidth to hurt Internet speeds. Apple Mac market share is small enough (through growing) to not hurt anyone not owning a Mac. This really isn't a true new worm. Anyone getting you to install a new app that partially passes gatekeeper can probably get you to install it and override gatekeeper. It's not that big of a leap.

I honestly feel bad at anyone angry at Apple selling too many computers. Do you need a cookie? Want to talk about it? Did your parents love you enough as a child?

Re:Doesn't matter.

[The-Ixian]

Yeah no kidding.

I don't personally like Apple the company. I just think they are too much about marketing hype. I was also not a fan of Steve Jobs personally.

But I still will recommend a Mac to someone when appropriate.

Computers and operating systems are tools not ideologies. Use the best tool for the job.

I won't be buying Apple products any time soon, but that is because there are tools out there that work better for me.

Re:Doesn't matter.

[ComputerGeek01]

Windows? Which is taking away control of your computer and sending analytics to the mother ship whether you agree or not?

As opposed to Apple where you never had any control over any of their devices to begin with? Apple IS the worst of all possibilities; they are overpriced, have ZERO support options outside of the "Mac Geniuses", nothing is documented and there is no ability to customize their software or tweak the system performance. You might be as happy as a pig in shit with a device that just does one thing adequately right out of the box and is useless for anything else, but this is a site for engineers; not social runoff that thinks it's too smart for Facebook.

Re: Doesn't matter.

[cyber-vandal]

Those options aren't available on OS X?

Re:Doesn't matter.

[Anonymous Coward]

But what else are people of a technical persuasion with no lives supposed to while away the hours of the day on? How will they maintain that false sense of superiority? That big bright thing in the sky burns, don't you know?!

Like another responder, I hate Apple the company with a burning passion of a thousand suns for actual wrongs done to me by middle and senior management level Apple employees. That said, I won't deny that, at least once upon a time, they built some great hardware and software. I think the glory days on both are well behind the company and it's only a matter of time before everyone else catches on, but they rightfully deserve credit for forcing everyone else to step up their quality game, giving us options besides a beige box and for being the first company with stones enough to kill off the floppy drive even if it was already years overdue by that point. Mac OS X also forced Microsoft to get serious about improving Windows, so out with GDI+ and in with Aero and the same basic thing with Android and even Windows Phone/Mobile and iOS. The competition, IMO anyway, has largely surpassed Apple who is now relying on the PITA factor of switching and getting new apps to keep users more than it'd care to admit, but they nonetheless deserve credit for forcing everyone to step up their efforts.

Re:Doesn't matter.

[Mattintosh]

Windows is far superior to Mac OS X. So is Linux.

Having been a user of all three, and a developer on all three, systems for many years, I actually know what I'm talking about.

I would readily recommend Windows workstations and, for some tasks, servers. I would readily recommend Linux for servers. I have written software for both. I would not recommend Macs for anything, as the hardware is unimpressive and not different from anything any other PC manufacturer makes, and the software is stifling and foam-padded so as not to be "unfriendly". Personally, I find that exact quality to be rather unfriendly in and of itself.

So if you need a Fisher-Price computer, and you feel you need to pay double the market rate for it, by all means, buy an Apple. And don't be too sad when your "new" computer is poorly supported, gets cut off from necessary updates, and bogs down under the "burden" of minor software updates over the course of the next two years. Everyone who has ever bought a Mac certainly understands your pain.

I used to be a fanboi like you, and if you don't believe me, check my username.

Re:Doesn't matter.

[Anonymous Coward]

Butthurt that your favorite PC maker's sales have been running downhill for years while Apple's keeps climbing? Or is it that it STILL isn't the year of Linux on the desktop & that it has become a sad joke?

Market share means nothing, and not all Linux users are neckbeards.

Re:Doesn't matter.

[The-Ixian]

Well said.

I don't think of Apple today as the same company they once were.

My first computer was an Apple II+ on which I spent countless hours wring BASIC programs. I monopolized its use so much that it eventually just ended up in my room. I would write basic by hand during boring church and couldn't wait to get home and type it in.

I loved that computer....

But Apple has always been expensive and it was much easier for me to buy PC components over time and slowly assemble a computer with my lawn mowing money. I have never really looked back.

Over the years I have looked at Apple products with envy at times. I think Mac has always been a good computer. It was just that by the time I could afford one, I was already well down the PC path. In addition to that, at the time, not much software worked with Mac and so it felt like it would be a step backwards.

That said, whenever I have the opportunity, I will use a Mac in order to be able to provide basic support.

I have a work issued iPad which I use for testing and playing some games. I like it ok, but it almost seems quaint compared to an Android table or a Microsoft Surface.

Re: Doesn't matter.

[Rosyna]

Have you never used a Mac? To change the default application for a camera, set it in Image Capture.app.

And, of course, idiots that think they know better can disable rootless. For those that know better, they install Perl or Ruby from source in a pace such as /usr/local/, which is designed for such installations and doesn't require disabling rootless.

Re: Doesn't matter.

[Rosyna]

It's these claims that make me wonder if you've used a Mac. It's easy to confirm on a Mac those claims are not true.

Yes, Image Capture settings most definitely stick. That's what is consulted when you plug in a camera device.

Again, /usr/local/ is explicitly excluded from rootless.

As for your Ruby/Perl issue. You're seriously trying to replace the system libraries first and third parties depend on? Why?! They were only ever tested with those system versions.

However, you can change the PATH by editing rc files or using the dscl tool.

Re:Doesn't matter.

[Guy Harris]

iOS runs UNIX and you have absolutely no control over it.

OS X is officially a UNIX but as of the latest version you can't even use root to replace some of Apple's software with newer versions.

If you're referring to System Integrity Protection, then, if you want to replace some of Apple's software, feel free to disable System Integrity Protection. A bit of a painful process, but the setting persists, so you only have to do it once, unless you want to turn it back on once you're done and then turn it off again when you want to change one of the protected files.

(Pro tip for people running OS X under VMware Fusion: if you're going to be doing this, you'll probably want to increase the boot delay on your VM so that you have enough time to do the "boot to Recovery OS" dance. The Parallels folk don't require anything like that, apparently, but I haven't tried it with Parallels.)

Lack of interest based security

[Flavianoep]

I've got the impression that security of MacOS relies strongly on the low market share and supposed lack of interest of the potential crackers. Am I too wrong?

Re:Lack of interest based security

[Flavianoep]

Yes.

OK. Thanks for your appreciation.

Re:Lack of interest based security

[Anonymous Coward]

No, you're right. But the other thing is that Gatekeeper isn't intended to keep OS X secure. It's intended to make running non-Apple code annoying and nothing more.

Keep in mind that in the Apple security model, you're not trying to protect the user from harmful code, you're trying to protect the computer from the user. The whole system is designed around preventing the user from doing things outside Apple's walled garden, not from preventing software from doing things it shouldn't be doing. As long as the average user can't run non-Apple code, from Apple's point of view, everything is working as intended. Even if a hacker CAN.

Re:Lack of interest based security

[dgatwood]

In any mode, you can run an unsigned or non-Apple-signed installer or app by control-clicking on it and choosing "Open".

Re:Lack of interest based security

[Guy Harris]

No, you're right. But the other thing is that Gatekeeper isn't intended to keep OS X secure. It's intended to make running non-Apple code annoying and nothing more.

To do that, it would have to be combined with making getting software from the Mac App Store, most of which is "non-Apple code", annoying. Presumably, then, you're saying that getting software from the Mac App Store is annoying.

Or perhaps you meant "it's intended to make non-Apple-approved code annoying", where "Apple-approved" means "approved by Apple to go into the Mac App Store". Whether that's the intent, yes, that's definitely a side-effect.

(I run non-App Store code quite a bit; for code installed by downloading a .dmg or installer package or..., it's a minor nuisance, and for stuff installed by downloading a source tarball, unpacking it, and doing the configure/make/make install dance or whatever that tarball requires, it doesn't come into play at all. At this instance, my biggest peeves with Apple software are 1) dealing with LLDB's misguided attempt to have a "better" command language than GDB and 2) having to teach Yosemite autocorrect that "sshd" isn't a typo for "sushi", "tarball" isn't a typo for "tarsal", etc.. :-))

Apple is New to Reacting to Security Threats

[bigal123]

Apple is new to reacting effectively to security. Microsoft gets beat up about security, but they have learned to attempt to react better. May not be perfect.

I know so many Apple people that think Apple immune security issues. I seriously wonder if we will see a day when Apple is is hit with the same type of security questions that have plagued Microsoft over the years.

Re:Apple is New to Reacting to Security Threats

[cant_get_a_good_nick]

To be honest, Apple is arguably better at this point than Microsoft was at a similar point in it's lifecycle, from a tech standpoint. Rootless MacOSX is a thing. Gatekeeper, though major holes, is a thing. It's just that back then, the Internet was not as much of a source of riches. There's never been a Slammer work for MacOSX. Nor a "I love you" virus.

You know who else had really bad security reputation? Redhat was horrible in the beginning. You know what famous developer doesn't pay enough attention to security? Linus Torvalds.

Not to skewer MS. Not to skewer Linus or Linux. But realize we're comparing relative bad here. The best OS from a security standpoint is just the least horrible OS on a security standpoint.

Security is hard. How do i patch an infinite state machine against people who can make a lot of money breaking it. It's not a trivial task.

Re:Apple is New to Reacting to Security Threats

[alvinrod]

Probably not.

The biggest issue right now as far as most people are concerned is javascript that hijacks a browser and tricks people into thinking their computer is completely locked up and that they need to call some tech support number to get it fixed. I recently had a relation call me about this because they didn't want to pay the $400 to get it fixed, which is what the website says they need to do.

All you need to do is just force quit the browser to fix the problem, but most people are too computer illiterate to know that. A short while after that, I saw a segment on the news about the exact same thing and warning people not to fall for the scam, because apparently hundreds of people had already been taken. You don't need to write complicated malware that exploits security holes in a system when you can be a shitty script kiddy and take advantage of people's lack of critical thinking.

What really perplexed me (besides the fact that what virus would advertise who to call in order to fix it) was that these people were claiming to be from Microsoft, but the person who called me had a Mac. It's far easier to just convince a stupid user to hand you their money or to install a program that will let them talk to horny singles in their area.

Most operating systems are fairly secure these days, but the weak point is still the people using them. If you're going to go to the trouble of exploiting some operating system security holes, you're far better off targeting an online retailer who has credit card information on file for thousands of people or enough of their personal information to facilitate identity theft. I don't expect we'll see the kinds of attacks that we used to see in the past with Windows. There are easier ways to make money from single targets that don't require security holes, and there are fatter targets that are more worthwhile to attack if you do find a security hole like that.

Re:Apple is New to Reacting to Security Threats

[SuiteSisterMary]

Been a while, but wasn't Slammer actually a SQL Server worm, and I love you was an email-based Trojan?

You're absolutely correct, however, in pointing out that in the age-old contest between warhead and armour, warhead wins.

Re:Apple is New to Reacting to Security Threats

[LichtSpektren]

Apple is new to reacting effectively to security. Microsoft gets beat up about security, but they have learned to attempt to react better. May not be perfect.

I know so many Apple people that think Apple immune security issues. I seriously wonder if we will see a day when Apple is is hit with the same type of security questions that have plagued Microsoft over the years.

Windows spent almost two decades with admin privileges by default 24/7, no mandatory-access control, installations that could occur silently and without user input, core system updates through the web browser, whilst also being the only real desktop PC operating system (i.e. it was the most lucrative target for malware authors). It's actually sort of miraculous that the security ecosystem wasn't in even worse shape than it was.

By contrast, OS X's origins in unix give it a fairly safe grounding. The keyring and SIP in El Capitan also seem to be quite robust. And Apple users are more trusting of automatic security updates compared to Windows users (Microsoft poisoned that well when they started pushing shitty drivers and malware through their updates).

Re:Apple is New to Reacting to Security Threats

[The-Ixian]

There are easier ways to make money from single targets that don't require security holes, and there are fatter targets that are more worthwhile to attack if you do find a security hole like that.

One thing that is missing from this equation is bot nets.

It certainly does benefit hackers to take over grandma's system if for no other purpose than to recruit it into the ranks of bitcoin mining, spam sending, ddos attacking, malware distributing, etc.

I guarantee you that if Apple was the dominant computing platform, it would have just as many issues as other platforms.

Re:Apple is New to Reacting to Security Threats

[dgatwood]

The biggest issue right now as far as most people are concerned is javascript that hijacks a browser and tricks people into thinking their computer is completely locked up and that they need to call some tech support number to get it fixed. I recently had a relation call me about this because they didn't want to pay the $400 to get it fixed, which is what the website says they need to do.

Agreed. I've gotten similar calls. And the problem is so simple that I can't believe Apple hasn't fixed it already (unless they have, and I just haven't noticed yet):

• Stop disabling the window close buttons while a JavaScript pop-up is visible (and when clicked, kill all active JavaScript and pop-ups associated with that window).
• Add a scroll view into JavaScript pop-up alerts so that it will be impossible for a malicious website to put so much text in an alert that the "Supress additional pop-ups from this window" bits end up below the bottom of your screen.

Re:Apple is New to Reacting to Security Threats

[pr0fessor]

I got a call at work the other day that I thought I recognized the number I was in a good mood and thought about answering "IT, have you tried turn it off and on again?" but settled for "Technical support, I'll be your password reset technician today."

Turns out it was a scammer claiming to be from MS... so after he said his intro I said "Yes, you've reach technical support. Do you need me to reset your password?" then he stammered and and tried to explain about how my computer was having issues and I said "Ok, I have reset your password but it will take about 15 minutes for the changes to go through. If you have any other issues go ahead and call back."

Re:Apple is New to Reacting to Security Threats

[Actually, I do RTFA]

To be honest, Apple is arguably better at this point than Microsoft was at a similar point in it's lifecycle, from a tech standpoint. Rootless MacOSX is a thing. Gatekeeper, though major holes, is a thing.

Same point in the lifecycle? Apple has been around, as a company in the OS business, as long/longer than MS. And things like rootless OSX are expectations, because people learn from other people;s experience.

I get that rewriting means there are needed patches. But when Apple wrote OSX, security was a real thing. And eliminating a lot of legacy code should prevent the source of a lot of issues.

The logic probably goes something like this...

[mamono]

GK: We don't need to do anything apart from just stop him entering the room.
OSX: No, no, leaving the room.
GK: Leaving the room, yes.
OSX: Alright?
GK: Right. Oh if if if uh if if uh if uh if we oh... if oh.
OSX: Look it's quite simple. You just stay here, and make sure he doesn't leave the room, alright?
GK: Oh I remember, uh can he leave the room with us.
OSX: No No No No. You just keep him in here and make sure h...
GK: Oh yes, we'll keep him in here, obviously. But if he had to leave, and we went with him...
OSX: No wait, just keep him in here,
GK: Until you or anyone else
OSX: No, not anyone else, just me
GK: Just you
OSX: Get back.

Working As Intended

[BitZtream]

Its working exactly as its supposed to. Its not meant to stop everything, its just a whitelisting system with some authentication built it.

Blacklisting the offending apps is exactly how this type of system works.

Anything signed by a valid cert which has been signed by Apple's cert is trusted by default. Thats what having an Apple signature on top of the publisher signature means. This also means the applications are 'tamper proof' in theory, because changing the application invalidates the sig and the code no longer is whitelisted, so no virus will work.

The system then keeps a CRL, Certificate Revocation List. This list is ... blacklisted fingerprints. That is, certs or specific apps that were not known to be compromised or malicious when Apple originally vetted them, but something became known to be compromised after that process. The CRL list means Apple can effectively change its mind about apps that it previously approved.

This is all it is intended to do, and that alone mitigates a metric fuckton of exploit cases.

Doesn't prevent apps that don't get caught in review. But you won't get more than one or two malicious apps past them before you're completely cut off from getting certs ever again. Vendors outside the AppStore will have their certs revoked when exposed in the wild.

At no point was it intended to prevent every single exploit vector ever. You're pretty ignorant of how this stuff works if you think they ever said it was the cure all to security issues.

All it does is adds a layer of control to who can run arbitrary code on your system, and by default, allows Apple to give people permission to do so. You can also use your own certs and remove the AppStore cert, effectively making it so only apps signed with your cert will run on the machine ... or in the case of some companies, the company's cert is the only thing that runs on the machine.

itwbennet == bennet haselton / dumb

Re:Working As Intended

[Anubis IV]

Indeed, the first thing I thought when reading this was, "What underlying issue? Blacklisting him is exactly how it's supposed to work."

Apps from trusted sources are supposed to be able to do pretty much anything they want until they prove they're not to be trusted. That's by design. And, inevitably, some developers will abuse that trust, which is why the design includes a means for the revocation of trust. Which is exactly what happened here.

Yes, he's shown that trusted devs can include external code that's malicious. So what? Trusted devs can also include internal code that's malicious. Either way, their certs will be revoked and the problem will go away. The primary benefit I can see is that this lets malware developers move their malicious code out of the bundle that goes through the App Store review process, but that's a marginal benefit at best, since the default Gatekeeper setting doesn't require apps to have gone through that process anyway.

Otherwise, the only other benefit is that this may allow someone to replace external libraries used be trusted apps outside of their control with libraries of their own design. E.g. Some video encoding apps require that you download additional libraries separately due to problems that arise with international copyright law, so you may be able to use this exploit to replace those libraries with malicious ones, thus turning a good app from a trusted developer into a vehicle for malware. That said, you'd need to provide a parallel exploit for replacing those libraries with your malicious ones before this would prove to be problematic.

Re:This story sounds familiar...

[ChrisMaple]

I am Zuul. I am the Gatekeeper.

It does when they buy it for work

[Sycraft-fu]

The reason I'm very anti-Apple is particularly our younger professors decide that they need to have apple computers, phones, and tablets to be hip. So they get them, against recommendations. Now never mind that these cost a lot more money than they'd spend on equivalent hardware but then the support issues start. Turns out that Mac don't just magically work, and they have problems with things (accessing the central storage is something Macs have been particularly problematic with) and they whine to us despite promising that they understand and will support things themselves.

Apple wants to pretend to be good for the enterprise, but their enterprise features are garbage. So people get them, want them to integrate, they don't, and then they cry about it.

Re:Gatekeeper isn't about security

[Guy Harris]

Gatekeeper isn't for security. Gatekeeper is intended to make running non-Apple approved code just annoying enough to force most users to use the App Store rather than use non-Apple blessed code. As they've demonstrated with the latest OS X where not even root can write to /usr or /bin

Or, rather, where you have to go through an annoying procedure, involving two reboots, to write to /usr or /bin.

Microsoft Jobs

[wkwilley2]

I'm actually impressed that Apple named anything with "Gate" in it

Re:Gatekeeper isn't about security

[Guy Harris]

Or, rather, where you have to go through an annoying procedure, involving two reboots, to write to /usr or /bin.

If you think that's annoying, you should try working with SELinux some time.

I haven't tried actually working with it, but I've certainly been annoyed when it kept VMware's hgfs from working on Linux guests - it wasn't immediately obvious how to let it work. (I think my VMs running newer versions of Fedora don't have a problem with hgfs, so maybe either VMware or the SELinux people fixed it.)