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A persistent denial of service vulnerability affecting iOS

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Re: A persistent denial of service vulnerability affecting iOS

#11

Post by userbinator »

Lammy wrote: post #8
masklinn wrote: post #5

Uh. I wonder if this can still be triggered when the Home application has been removed from the device? I expect so as IIRC builtin-in application removal is really just hiding them and all the functions are part of priviledged bundles shipped with the OS.

> all the functions are part of privileged bundles shipped with the OS Luckily a lot of these can be disabled when jailbroken: https://i.imgur.com/KhGmGrf.png

It's unfortunate that you need to exploit a (different) vulnerability in order to gain full control of your devices.

Re: A persistent denial of service vulnerability affecting iOS

#12

Post by pxeboot »

sebastien_b wrote: post #9

There are so many bugs in iOS that are years old and still unfixed. One example is the cellular-data draining bug[1]. The only "solution" for this is to wipe your device, and set it up again, without restoring any backups, at all. Which makes the whole point of backups of the device totally pointless. For a company that spent $6B+ on a (now mostly empty) campus, you'd think they could spare a few $million into proper…

> Which makes the whole point of backups of the device totally pointless.

Isn't this exactly how backups should work? Do you really want Apple deciding which settings/data are not important to you?

Re: A persistent denial of service vulnerability affecting iOS

#13

Post by sebastien_b »

pxeboot wrote: post #12
sebastien_b wrote: post #9

There are so many bugs in iOS that are years old and still unfixed. One example is the cellular-data draining bug[1]. The only "solution" for this is to wipe your device, and set it up again, without restoring any backups, at all. Which makes the whole point of backups of the device totally pointless. For a company that spent $6B+ on a (now mostly empty) campus, you'd think they could spare a few $million into proper…

> Which makes the whole point of backups of the device totally pointless. Isn't this exactly how backups should work? Do you really want Apple deciding which settings/data are not important to you?

The backups aren't the problem - what is the problem is Apple's "solution" to a clear bug being "don't restore from backups" (for the cellular-data draining bug).

Instead of asking you to lose all your data as a workaround to a bad bug, they should actually fix that bug properly, so that it's no longer a bug.

Likely the same with the bug described in this story - if someone ends up affected by it, they're basically pooched: they can't do any more new backups, and likely if they do restore from a previous backup where data exists that triggers this, they're just going to get into that same loop of problems.

And because it's not a "high severity" (RCE) bug, it's likely never really going to get fixed as there are "workarounds for it" (read: wipe/setup the device and omit your data) or "other mitigations implemented already (previous versions of the OS be damned!)" as noted in the story.

Re: A persistent denial of service vulnerability affecting iOS

#14

Post by dv_dt »

pxeboot wrote: post #12
sebastien_b wrote: post #9

There are so many bugs in iOS that are years old and still unfixed. One example is the cellular-data draining bug[1]. The only "solution" for this is to wipe your device, and set it up again, without restoring any backups, at all. Which makes the whole point of backups of the device totally pointless. For a company that spent $6B+ on a (now mostly empty) campus, you'd think they could spare a few $million into proper…

> Which makes the whole point of backups of the device totally pointless. Isn't this exactly how backups should work? Do you really want Apple deciding which settings/data are not important to you?

No but it would be nice to be able to selectively restore a subset of backups.

Re: A persistent denial of service vulnerability affecting iOS

#15

Post by aaomidi »

pxeboot wrote: post #12
sebastien_b wrote: post #9

There are so many bugs in iOS that are years old and still unfixed. One example is the cellular-data draining bug[1]. The only "solution" for this is to wipe your device, and set it up again, without restoring any backups, at all. Which makes the whole point of backups of the device totally pointless. For a company that spent $6B+ on a (now mostly empty) campus, you'd think they could spare a few $million into proper…

> Which makes the whole point of backups of the device totally pointless. Isn't this exactly how backups should work? Do you really want Apple deciding which settings/data are not important to you?

Is this how backups work with your personal computers?

Re: A persistent denial of service vulnerability affecting iOS

#16

Post by pxeboot »

aaomidi wrote: post #15
pxeboot wrote: post #12

Earlier quoted context omitted.

> Which makes the whole point of backups of the device totally pointless. Isn't this exactly how backups should work? Do you really want Apple deciding which settings/data are not important to you?

Is this how backups work with your personal computers?

Yes, if I do a full restore, I expect all files and settings to be restored, including bugs present at the time the backup was made.

Re: A persistent denial of service vulnerability affecting iOS

#17

Post by yegle »

pxeboot wrote: post #16
aaomidi wrote: post #15

Earlier quoted context omitted.

Is this how backups work with your personal computers?

Yes, if I do a full restore, I expect all files and settings to be restored, including bugs present at the time the backup was made.

iOS backup apparently doesn't work like you described. E.g., when restoring a backup from iOS 14, it doesn't revert your system to iOS 14. Clearly there's a separation of restoring the executables and restoring the configs.

I do expect "the config/setup that would trigger a battery drain in =iOS X.

Re: A persistent denial of service vulnerability affecting iOS

#18

Post by sodality2 »

userbinator wrote: post #10
Apocryphon wrote: post #7

Why didn’t they add a string limit?

Perhaps the limit was "available memory"? It's not hard to imagine how a programmer who has only ever worked with dynamic languages and basically doesn't know what a fixed-length-buffer is could be completely oblivious to it. Then again, what is an appropriate limit on the length of the name of a HomeKit device? I'm tempted to say 255, but I'm sure someone else would disagree. I've been in design meetings where such…

I can't imagine anyone would disagree with 1024 characters.

Re: A persistent denial of service vulnerability affecting iOS

#19

Post by aaomidi »

pxeboot wrote: post #16
aaomidi wrote: post #15

Earlier quoted context omitted.

Is this how backups work with your personal computers?

Yes, if I do a full restore, I expect all files and settings to be restored, including bugs present at the time the backup was made.

If you do a full restore implies that you don't have to do that.

And yeah as the other commenter said, that's not really how the ios one works.

Re: A persistent denial of service vulnerability affecting iOS

#20

Post by Nextgrid »

masklinn wrote: post #5

Uh. I wonder if this can still be triggered when the Home application has been removed from the device? I expect so as IIRC builtin-in application removal is really just hiding them and all the functions are part of priviledged bundles shipped with the OS.

Built-in apps are merely frontends, the actual functionality is tightly integrated into the OS in the form of daemons running in the background. I very much doubt removing the frontend app disables any of the daemons, especially considering these can be used to provide APIs that apps may rely upon.
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