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FaceTime bug lets you hear audio of person you are calling before they pick up

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Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#381

Post by auiya »

mcpherrinm wrote: post #246
NelsonMinar wrote: post #13

I'm always curious how a bug like this ships. I mean QA & Testing should catch it, sure. But even before then. Some engineer wrote code for FaceTime that has it open the microphone before the call is accepted. And transmit the audio over the network before the call is accepted. Who did that? And why? I'm not suggesting malice but I do wonder at the lack of defensive programming.

This seems like a state machine bug to me. If you consider what happens when you add a third person to a call: You start sending them everyone's audio! That's the desired behavior and exactly what happened here. Except the client should have probably checked if the call had been accepted first. That's why I say it's a state machine bug: The "Send audio" function should have never been activated in state "waiting to a…

> If you consider what happens when you add a third person to a call: You start sending them everyone's audio!

Not before they accept the call connection request you don't.

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#382

Post by JangoSteve »

NelsonMinar wrote: post #13

I'm always curious how a bug like this ships. I mean QA & Testing should catch it, sure. But even before then. Some engineer wrote code for FaceTime that has it open the microphone before the call is accepted. And transmit the audio over the network before the call is accepted. Who did that? And why? I'm not suggesting malice but I do wonder at the lack of defensive programming.

I'm wondering if it's something really simple, like comparing the unique number of callers versus the total number who have accepted the call.

Imagine a method for group calling that returns whether or not the call should be considered active or not by seeing if the number of callers is equal to the number who have accepted the call. But now imagine the method that tallies up the number of callers does a unique count by phone number, while the method that tallies how many people have accepted the call does not.

Since adding your own number is adding a caller who has already accepted a call, you end up with unique_callers (2, you and them) == total_accepted (2, you and you).

This could be tested by adding a third person to a group call twice (if iOS will let you do that) instead of adding yourself to the call.

Furthermore, if the interface on the recipient's phone only looks at whether or not they've accepted the call, that would explain why the call doesn't auto-accept on their end and go into the call before they've accepted or rejected the call.

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#383

Post by freehunter »

akerl_ wrote: post #186
paxys wrote: post #163

Earlier quoted context omitted.

Well this is the top Twitter trend right now, for starters. It's a very visible, very easy to reproduce bug in a very popular service, and it's definitely going to hurt their reputation with consumers more than if it was something more technical yet equally or more dangerous.

Again, are there examples that show it will “definitely” hurt their reputation at all? I’ll broaden my example set: are there any examples of consumer devices where the company suffered clear damage to their brand as a result of a security issue?

As an information security professional I wish security breaches would permanently damage a company's reputation, and even put some companies out of business if the breach demonstrates they have no business handling sensitive personal information. But if that was the case, Target and Home Depot and Equifax wouldn't exist, and no one would dare touch an Android phone or a Windows computer.

The sad fact is consumers don't care one bit. The only people who care are people who have some interest in disliking the company who was breached, in which case they're likely not paying customers anyway.

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#384

Post by swat535 »

pbhjpbhj wrote: post #359
whamlastxmas wrote: post #354

Earlier quoted context omitted.

I think it's much more likely their code is a mess and it's not super obvious when stuff starts and ends and this is just an unintentional mistake.

You hear this excuse all the time, don't FAANG employ the world's very best developers? Maybe their code is a mess for orthogonal reasons - management, profit-motive? Aside: I thought I'd heard devs have automated analysers that step through and find all possible code paths, allowing complex code to be audited for security issues and such? Presumably that's how these sorts of bugs should be found in testing.

Since they have an impeccable interview process that only selects the brightests.. They may be all too busy implementing linked lists and inverting binary trees instead of actually delivering a working product.

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#385

Post by acct1771 »

ethbro wrote: post #371
MagicPropmaker wrote: post #364

Earlier quoted context omitted.

Also, HN won't comment on how/why Apple insists that iOS is "secure by design". I've brought this up and it gets buried. Why? https://www.apple.com/business/resources/docs/iOS_Security_O... This phrase is used several times on their current website: https://www.google.com/search?q=%22secure+by+design%22+site%...

Because they're well documented as having a more robust hardware/software security model than the dumpster fire that is Android security?

Wait, what's wrong with F-Droid, exactly?

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#386

Post by sonnyblarney »

pbhjpbhj wrote: post #359
whamlastxmas wrote: post #354

Earlier quoted context omitted.

I think it's much more likely their code is a mess and it's not super obvious when stuff starts and ends and this is just an unintentional mistake.

You hear this excuse all the time, don't FAANG employ the world's very best developers? Maybe their code is a mess for orthogonal reasons - management, profit-motive? Aside: I thought I'd heard devs have automated analysers that step through and find all possible code paths, allowing complex code to be audited for security issues and such? Presumably that's how these sorts of bugs should be found in testing.

great developers with with bad process, quick turnaround, lack of ownership and bad habits can lead to a mess.

Also - maybe they inherited the code from a startup and never had the chance to refactor and so there was a mess from the start.

Either way, bugs happen. Of all kinds, even bad ones'.

More circumspect than a 'bug' is that this got through their tests. Their end-to-end testing should have picked this up.

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#387

Post by notfed »

basil-rash wrote: post #228
notfed wrote: post #169

Earlier quoted context omitted.

Yup. Or, at the least, have a separate switch that does so.

That went from "two transistors" to "an entirely separate physical component on the chassis" pretty quickly.

He/she didn't like the first suggestion. (Actually, it seems most people commenting here don't. Apparently I'm in the minority on this one.)

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#388

Post by notfed »

AmericanChopper wrote: post #214
notfed wrote: post #137

Earlier quoted context omitted.

iPhones already have a "mute" slider switch. When I first looked into iPhones (after years of Androids), my instant reaction upon seeing the slider switch was "Ah! FINALLY! I can feel at peace in the knowledge that software vulnerabilities are powerless to hack my camera or microphone!" Of course, stupidly, the slider doesn't "mute" my camera or microphone, but only my speaker. For Apple to modify this slider so that…

I have my phone muted for most of the day, but I still want to be able to take pictures and use siri. It doesn’t even mute the speakers, only notifications. It sounds like you want to replace a switch that many people want to use, with one that few would.

I also have it muted most of the day; usually all day. Which effectively makes it useless as it is. Perhaps this puts me in the biased position of feeling it may be used for another purpose.

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#389

Post by [deleted] »

jodrellblank wrote: post #294
kennywinker wrote: post #155

Earlier quoted context omitted.

Frankly, I’m totaly in favour of hardware interrupt switches for the camera/mic - but I think I understand why it’s not likely to happen. First, to a lot of people it will look like admitting your thing is hackable, which makes it seem vulnerable. Second, now every time I accept a call I have to check this switch - sounds like a switch most people will leave in the on-position 100% of the time and then when it accide…

sounds like a switch most people will leave in the on-position 100% of the time and then when it accidentally gets flicked they’ll bring their phone to the Apple store because “it’s broken”. laptops with hardware wifi and bluetooth switches. Took plenty of support calls about those.

[deleted]

Re: FaceTime bug lets you hear audio of person you are calling before they pick up

#390

Post by jasallen »

brownbat wrote: post #345
yalok wrote: post #255

Earlier quoted context omitted.

My guess is that it’s an unfortunate combination of several problems: - audio and video capture has to start going before call is actually established at signaling level, in order to minimize call establishment delay. Audio maybe going through Bluetooth, for example, and waking up Handsfree mode of BT may take 1-2 sec - most of the group calling functionality was developed by a separate team, and group calling signal…

They were trying to reduce a latency and accidentally made it negative.

"negative latency". That's a Jobs worthy dodge right there.
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