OS X Mountain Lion Limits Apps to Mac App Store, Signed Apps by Default

One of the significant new features in OS X Mountain Lion is Gatekeeper, a new security system to help keep users from installing nefarious applications on their machines.

The new system relies not only on Mac App Store distribution as means of vetting apps, but also on a new "identified developer" program under which developers distributing their applications outside of the Mac App Store can register with Apple and receive a personalized certificate they can use to sign their applications. Apple can then use that system to track developers and disable their certificates if malicious activity is detected.

As Macworld notes in its review of Gatekeeper, OS X Mountain Lion's default setting will be to only allow initial launching of apps either downloaded from the Mac App Store or which are digitally signed under Apple's identified developer program. Users will be able to access Gatekeeper's settings in the Security & Privacy section of System Preferences, where they will also be able to choose from an even stricter setting that will allow for installation of Mac App Store apps only or a looser setting that will allow all applications to be installed and launched.
Located in the General tab of the Security & Privacy preference pane is a setting called “Allow applications downloaded from,” with three options:

Anywhere: This choice uses the same set of rules as every previous version of Mac OS X. If an app isn’t known malware and you approve it, it opens.

Mac App Store: When this choice is selected, any apps not downloaded from the Mac App Store will be rejected when you try to launch them.

Mac App Store and identified developers: This is the new default setting in Mountain Lion. In addition to Mac App Store apps, it also allows any third-party apps that have been signed by an identified developer to run.
For users on the default setting, they can bypass the initial Gatekeeper check the first time they launch an unsigned third-party app by right clicking on the app itself and choosing the "Open" command. Once the application has been opened one time, Gatekeeper no longer has any control over it.

As for apps that are signed by an identified developer, Macworld notes that OS X Mountain Lion will perform a daily check with Apple's servers for blacklisted developer signatures, and if an app from a blacklisted developer is installed on the user's system it will not open.

Importantly, Apple's identified developer program does not involve any sort of vetting on Apple's part, as certificates are automatically issued upon request and can be freely used by the developers. But what the program does do is provide a way for Apple to link specific developers to specific apps and use Gatekeeper to revoke application functionality should a developer be discovered to be distributing malware.

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105 months ago
Why do some people take half the facts and cry?
Rating: 32 Votes
105 months ago

Well we all knew this was coming. After Mountain Lion we'll have to jailbreak to run apps from outside the App Store.

No we won't. You just need to turn down the setting to allow all apps.
Rating: 22 Votes
105 months ago
I knew I shouldn't have looked at this thread... immediately full of "Goodbye OS X" posts.

Gatekeeper really does seem like an intelligent approach to security in OS X. If anything, I think it re-affirms that OS X will not be Mac App Store only for the foreseeable future. Apple is giving developers an opportunity to play nice, without all the headache and restrictions placed on distributing through the Mac App Store.

Gatekeeper, IMHO, feels like a "we get it - it's not iOS" from Apple. In fact, I'm hoping for Gatekeeper to show up in iOS 6.
Rating: 18 Votes
105 months ago

Why do some people take half the facts and cry?

Complaining is fun! :D
Rating: 16 Votes
105 months ago

Image (http://obamapacman.com/wp-content/uploads/2011/02/Bill-Gates-Big-Brother-Apple-1984.jpg)


You may wanna go and check the Gatekeeper developer meaning again.

As much as a geek I am, I am probably gonna run the OS in Mac App Store only Gatekeeper mode and revert to Anywhere when I need to install some stuff on the web.

This is the best Apple can do for the very vast number of users. Caters to us geeks, caters to normal people and caters to those who don't know the **** they are doing.

This is unbelievably awesome.

Well we all knew this was coming. After Mountain Lion we'll have to jailbreak to run apps from outside the App Store.

On the contrary, this is evidence that Apple is NOT going to close the Mac. Things cannot be much more obvious for those who really wish to see without bias and hatred.

Short story for those interested:
Just a couple of days back, one of my friends referred to this concept in general and I was so blown away (shame I couldn't figure out myself). This also prevented Apple from changing the underlying UNIX system to an extent where they would revoke installation permissions from the user or admin or even the super-user. Maybe an additional private kernel model only used for app installations.

This is absolutely surreal. Best ****in feature ever. People don't realise this but this makes me believe that Apple is running for the geeks too. Long live Apple.
Rating: 13 Votes
105 months ago

Yes, in Mountain Lion. But I was saying that Apple will silently phase that out in the next release.

I will remain an optimist for now. In some respects, I like the GateKeeper concept. However, if Apple removes (or hides) the "anywhere" feature in 10.9 or higher, I will re-think my OS of choice (but *still* won't consider Windows). When malware can get onto my machine and install like machine-gun fire (this is on a corporate network with "enterprise-level" anti-malware software) when I don't even have admin access myself to install anything, MS will never have my business. I guess I'll revisit (and learn) Linux at that point.
Rating: 10 Votes
105 months ago
One important note is this will make Macs an even more unattractive target for cybercriminals.

* Gatekeeper is enabled by DEFAULT, most users won't and don't know how to change default settings

* Power-users who disable Gatekeeper are probably already cognizant about malware and won't likely be tricked into downloading it

Ergo, this makes the potential target area for malware attacks on Mac even smaller than it is now. It simply won't be worth the investment for cybercriminals to go after Macs.

Gatekeeper is a primary deterrent against malware like MacDefender. Remember how the cybercriminals would release a new variant immediately after Apple added the last one to the Xprotect blacklist? Gatekeeper nixes that strategy. Gatekeeper + Xprotect makes Macs damn near invulnerable to malware when you think about it, and this even takes the "dumb user" factor into account.

Smart move, Apple.
Rating: 9 Votes
105 months ago
i highly doubt apple will completely lock down OS X from non mac app store app's. They are simply making the machine more secure to the average user. It's not hard to allow other apps and im sure if you try and open one downloaded elsewhere it will tell you exactly how to allow it. This just pretty much makes it so any malware would have to be signed for it to open on a mac with the default setting, imo better for the average user
Rating: 9 Votes
105 months ago
I got worried reading this, but as long as there's an option to disable this I'm fine with it. However the day they start limiting apps to Apple Approved Digitally Signed applications only... is the day I sell off my Apple products. I run Windows, Linux, and OS X daily and have no problem doing it, if push comes to shove.


For the record I'm not complaining. I think someone like my grandmother would benefit greatly from having the applications she installs on her computer monitored. As long as there's an opt out feature for people who know what they're doing, that's all I ask for as a customer.
Rating: 9 Votes
105 months ago
But no iBooks? :(
Rating: 8 Votes

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