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Hidden backdoor API to root privileges in Apple OS X

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211–220 of 367 posts

Re: Hidden backdoor API to root privileges in Apple OS X

#211
It does explicitly say that Security Update 2015-004 only updates Admin Framework on 10.10+ (it does not require 10.10.3) to fix CVE-2015-1130 : Emil Kvarnhammar at TrueSec https://support.apple.com/en-us/HT204659

Quite a few other security related things are fixed with this update that do apply to older versions of OS X.

Re: Hidden backdoor API to root privileges in Apple OS X

#212
post #105

Earlier quoted context omitted.

What kind of issues? I've literally noticed no differences besides UI.

FWIW, 10.10.0 for me was perfect. 10.10.1 broke my wifi. Anytime the computer woke up from sleep, I'd have to reset the wifi card so it could find my access point. After 10.10.2 came out, I got my second-ever full computer lock-up. I've had the same OS image since 10.5 (migrated and upgraded multiple time, obviously) and this was the second time my computer required a hard reboot. And this was while watching a video…

'Windows signature edition' sides steps the crapware on purchase that most OEMs have. You can buy the machines in the microsoft store.

Re: Hidden backdoor API to root privileges in Apple OS X

#213

Earlier quoted context omitted.

> Windows is out of the question after seeing what a factory OEM image comes with nowadays. I'm not giving them money and spending 2 days formatting/reinstalling/seeking out drivers on slow Taiwanese servers just to make a half-usable computer. And then, after all that, spend another 2 days installing various adware infested shitware to get a fricking PDF viewer. Microsoft Signature PCs solve this problem. :) http://…

Don't know how many of these are at, say, Costco. Which is where many people shop. I'm never buying a Windows laptop, so it doesn't affect me, but I'm still the resident "family IT specialist". And I know, I just know I'm going to be asked lots of questions I don't have the patience for, as these poor bastards wonder why their computers are slow, all because the shitty OEM wanted to make a few cents off pre-installed…

> It's like a car manufacturer selling you a car with a "feature" that takes away 50 HP to play a jingle every time you turn on your headlights, all because the got paid $7.34 by the jingle manufacturer.

Not that bad, but my car does come with what amounts for an advertisement for Sirius Radio built in.

:(

I was also offered a TON of extra add-ons when I bought my car. I'd say it was roughly equivalent to the process of setting up a new low-end PC in regards to the number of ad requests I got.

On the PC side, this is all typically mitigated by not buying the cheapest PC possible. In my experience (and this is not universally true!) the higher end SKUs are more customer centric, since at that point the customer is the one paying the entire cost of the device!

(See also, Nexus devices versus carrier branded phone models!)

Re: Hidden backdoor API to root privileges in Apple OS X

#214
post #194
post #143

Earlier quoted context omitted.

>Yet many comments here are saying that people should just upgrade while it might solve the problem for some, there are ones who can't upgrade machines at will. It's dumbfounding how people here are simply shrugging this off and posting "So what? Just upgrade. Simples" type comments. This isn't acceptable. I know many people in creative industries alone who can't just upgrade immediately any time something comes out…

I have 3 macs. One of them is an older iMac. I can't put enough RAM in it to run Mavericks (which is a memory hog). It is a perfectly good computer, there is no reason to upgrade from Lion. The next one is a 3 year old Mac Mini. I upgraded to Yosemite and it performs TERRIBLY. It has 16G of RAM. I've tried everything. Yosemite just sucks. The machine is now much slower than the 6 or 7 year old iMac with only 4G or RA…

"I can't put enough RAM in it to run Mavericks (which is a memory hog)."

I'd upgrade to Yosemite today with the latest updates. They just freed up 4 GB of ram for me. Sadly if I had known all of this beforehand I wouldn't have gone out of the way to buy some old Mac Pro where I could upgrade the memory to 32 GB or more, so I just wasted about $1500 for the whole setup.

Then again like you, I transitioned my work to an Ubuntu box, but even for my personal stuff my Mac was just really slow unless you get an SSD drive which is time consuming to install on an iMac.

Re: Hidden backdoor API to root privileges in Apple OS X

#215

Earlier quoted context omitted.

I'm kind of surprised there's not a means (to my knowledge, at least) to crash/throw an exception upon sending a message to nil for people who want to better ensure their code doesn't have lurking issues like this. I suppose it'd have to be smart enough to filter out system frameworks to be useful, but I'd imagine that to be do-able.

Why not just some old-fashioned input guarding? if (input == nil) haltAndCatchFire(); Or whatever the Objective-C syntax for that is.

To make a scheme like that work, you'd essentially need to check before every single method invocation in your entire program because the issue — such as it is — is with method invocations being made against nil references, not with nil parameters being passed in as arguments to method calls.

I was imagining something more like a modified version of the runtime's objc_msgSend() C function (which Obj-C method invocations get compiled into) that guarded against that, but you do make me realize that such checks could conceivably be automatically tacked on at build time.

Anyway, I'm not entirely sure how useful such a thing would be, but I am curious how often my code (unintentionally) makes calls against nil and I've just never noticed because it doesn't cause harm.

Re: Hidden backdoor API to root privileges in Apple OS X

#216
post #111
post #69

OT but I have to say that the amount of Apple apologists in these comments is mind blowing. HN reader of all people should be the ones urging Apple to issue a fix for a very serious bug such as this one. Yet many comments here are saying that people should just upgrade while it might solve the problem for some, there are ones who can't upgrade machines at will.

Yeah, this is scandalous. I've heard enough things about Yosemite bugs that I held off upgrading, especially as I want to avoid software compatibility issues. I hate Apple's new yearly release cycle. There's not enough time to stabilize and improve OS's. This update just rolled out, but it indicates the admin fixes are only for Yosemite: https://support.apple.com/en-us/HT204659 How worried should I be about not havin…

Is your mac a server or a multi-user desktop where some users intentionally don't have admin access? If so, you're in trouble. If not, this bug probably doesn't really matter to you.

For a single-user desktop machine, realistically, user/root privilege separation doesn't matter, because all your important data is in your home directory and not protected by root privileges anyhow. The root-protected stuff is actually the stuff that's easiest to replace, because it's just a bunch of software that you can re-install. Viruses don't need to infect your software to stay resident; they can just as easily register a login hook without root permissions.

(That said, some people will violently disagree with me on this.)

Re: Hidden backdoor API to root privileges in Apple OS X

#217
post #165

Earlier quoted context omitted.

> To be fair, OS X updates are free and usually run well even on 5+ years old hardware Unless your hardware has been made "incompatible" by Apple (not for any technical reason, but simply because they wish you'd buy new hardware).

What hardware have they dropped support for without a technical reason? To my knowledge, the only Intel Macs they've dropped support for are ones with 32-bit processors, 32-bit firmware (requiring a 32-bit kernel and drivers even if the processor is 64-bit), or really old GPUs that can't support recent versions of OpenGL.

To my knowledge no Linux distro packages install media supporting 32-bit firmware and 64-bit kernel+CPU, but it's definitely possible to built a 32-bit GRUB EFI binary and have it load and execute a 64-bit kernel on a 64-bit CPU. I've done it on such a Mac. And there are a number of tablets built this way also (unfortunately).

Re: Hidden backdoor API to root privileges in Apple OS X

#218
post #4

Title is a little generous about "hidden", the exploit revolves around API & Framework used to power the parts of the control panel, and its authorization scheme being broken. I do think its too bad that setuid binaries don't have additional restrictions, like 100% must be code-signed or must be run in a sandbox-exec[1] based on that signing. [1] - https://developer.apple.com/library/mac/documentation/Darwin...

Isn't the "hidden" part related to them being a private API/Framework?

Re: Hidden backdoor API to root privileges in Apple OS X

#219

Earlier quoted context omitted.

> Windows is out of the question after seeing what a factory OEM image comes with nowadays. I'm not giving them money and spending 2 days formatting/reinstalling/seeking out drivers on slow Taiwanese servers just to make a half-usable computer. And then, after all that, spend another 2 days installing various adware infested shitware to get a fricking PDF viewer. Microsoft Signature PCs solve this problem. :) http://…

Don't know how many of these are at, say, Costco. Which is where many people shop. I'm never buying a Windows laptop, so it doesn't affect me, but I'm still the resident "family IT specialist". And I know, I just know I'm going to be asked lots of questions I don't have the patience for, as these poor bastards wonder why their computers are slow, all because the shitty OEM wanted to make a few cents off pre-installed…

Just do clean install. I always do it on friend's new laptops. 10 minutes. Saves lots of time later.
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