Apple patches vulnerability where iPhone & MacBook cameras could be hijacked

Posted:
in General Discussion edited April 2020
An ethical "white-hat" hacker exploited Apple's own apps in December to show how a malicious website could gain unrestricted access to a user's camera and microphone without consent using flaws that have since been patched.

Hacker uncovered exploits capable of hijacking iPhone, MacBook cameras


Former Amazon Web Services security engineer, Ryan Pickren, discovered seven zero-day vulnerabilities in Apple's Safari that could be used to hijack users' cameras. The vulnerabilities exploited the way Safari parsed Uniform Resource Identifiers, managed web origins, and initialized secure contexts.

The only requirement was that the user's camera would have had to trust a video conferencing site, like Zoom. If that criteria was met, a user could visit a site that utilized the attack chain, and a hacker could gain access to a users camera -- both on iOS and macOS.

Pickren had submitted his research to the Apple Bug Bounty program and was paid $75,000 for his contribution. Apple fixed three of the security flaws -- the ones that allowed for camera hijacking -- in the January 28 Safari 13.0.5 update. The four remaining flaws were not fixed until the Safari 13.1 release on March 24.

"A bug like this shows why users should never feel totally confident that their camera is secure," Pickren told Forbes, "regardless of operating system or manufacturer."

Pickren had discovered the bug by "finding assumptions in software and violating those assumptions to see what happens." He noted that the camera security model was difficult to crack, as Apple requires nearly every app to be granted explicit permission to the microphone and camera. This makes it far less likely that a malicious third-party app could gain access without a users express permission.

The exception to the rule, however, is Apple's own apps, such as Safari. Pickren was able to exploit this exception to uncover the bugs. He managed to "hammer the browser with obscure corner cases" until he gained access to the camera.

Comments

  • Reply 1 of 13
    lkrupplkrupp Posts: 10,557member
    Okay, so I  think I read way back that my iMac’s camera and indicator light were tied together and one could not activated without the other. Did I imagine that or am I right?
    caladanianjony0
  • Reply 2 of 13
    I’d like to know as well. I hope it is.  It should be done in hardware without any programmable hardware in between. 
    jony0
  • Reply 3 of 13
    seanismorrisseanismorris Posts: 1,624member
    Re: "A bug like this shows why users should never feel totally confident that their camera is secure," 

    Let’s see them hack through my electrical tape.  

    mwahahaha
    muwhahaha
    muahahaha
    bwahahaha
    baconstangdysamoria
  • Reply 4 of 13
    MplsPMplsP Posts: 4,007member
    lkrupp said:
    Okay, so I  think I read way back that my iMac’s camera and indicator light were tied together and one could not activated without the other. Did I imagine that or am I right?
    I remember reading that, too. I found this thread discussing it that seems to say it may have been possible on the the older (i.e. > 10 years old) cameras but in the newer modules the LED is directly wired to the camera module's power supply.
    razorpitchiaStrangeDayscaladanianjony0dysamoria
  • Reply 5 of 13
    razorpitrazorpit Posts: 1,796member
    MplsP said:
    lkrupp said:
    Okay, so I  think I read way back that my iMac’s camera and indicator light were tied together and one could not activated without the other. Did I imagine that or am I right?
    I remember reading that, too. I found this thread discussing it that seems to say it may have been possible on the the older (i.e. > 10 years old) cameras but in the newer modules the LED is directly wired to the camera module's power supply.
    There should be an indicator like that for iOS devices.

    Does anyone know if this vulnerability was able to activate without turning on the LED on newer Macs?
    caladaniandysamoria
  • Reply 6 of 13
    Rayz2016Rayz2016 Posts: 6,957member
    razorpit said:
    MplsP said:
    lkrupp said:
    Okay, so I  think I read way back that my iMac’s camera and indicator light were tied together and one could not activated without the other. Did I imagine that or am I right?
    I remember reading that, too. I found this thread discussing it that seems to say it may have been possible on the the older (i.e. > 10 years old) cameras but in the newer modules the LED is directly wired to the camera module's power supply.
    There should be an indicator like that for iOS devices.

    Does anyone know if this vulnerability was able to activate without turning on the LED on newer Macs?
    No, according to Gruber.  Since 2008 it has not possible to activate the camera on a Mac without activating the light. The light and the camera are cabled together. If you cut the wire, the camera won’t work, and there is no firmware between them so it can’t be hacked. 

    https://daringfireball.net/2019/02/on_covering_webcams

    But he also notes that a quick frame grab might be so fast that you might not notice the camera light has been lit. 

    So I think we still need something a little more permanent to say the camera was on. 
    edited April 2020 StrangeDaysCloudTalkinrazorpitcaladanianjony0dysamoria
  • Reply 7 of 13
    razorpitrazorpit Posts: 1,796member
    Just leave an indicator on for a little bit just like location services do. Go one step further, have one for the microphone too! That might surprise a lot of people.
    cgWerksdysamoria
  • Reply 8 of 13
    cgWerkscgWerks Posts: 2,952member
    Re: "A bug like this shows why users should never feel totally confident that their camera is secure," 
    Let’s see them hack through my electrical tape.  
    Or my Mac mini with the Logitech webcam. Pull out the USB plug and then let them hack it. :smiley: 
    And, it's a better webcam too!

    AppleInsider said:
    He noted that the camera security model was difficult to crack, as Apple requires nearly every app to be granted explicit permission to the microphone and camera. This makes it far less likely that a malicious third-party app could gain access without a users express permission. 
    The exception to the rule, however, is Apple's own apps, such as Safari. Hmm, but doesn't Safari pass out those permissions on a site-by-site basis? I was just trying to get some video-conferencing software working for an upcoming dr appointment, and it just wouldn't work with Safari, because it kept claiming it couldn't access the camera (it asked for mic access, but must be buggy about asking for camera). I finally had to give up and use Chrome... which scares me a bit, because then who knows what Chrome gives out that access to. (Of course, I hardly ever use Chrome except for such instances, so that should be OK.)
  • Reply 9 of 13
    Rayz2016Rayz2016 Posts: 6,957member
    Some information from Daring Fireball concerning the microphones. 

    https://support.apple.com/en-gb/guide/security/secbbd20b00b/web

    All Mac portables with the Apple T2 Security Chip feature a hardware disconnect that ensures the microphone is disabled whenever the lid is closed. On the 13-inch MacBook Pro and MacBook Air computers with the T2 chip, and on the 15-inch MacBook Pro portables from 2019 or later, this disconnect is implemented in hardware alone. The disconnect prevents any software—even with root or kernel privileges in macOS, and even the software on the T2 chip—from engaging the microphone when the lid is closed. (The camera is not disconnected in hardware, because its field of view is completely obstructed with the lid closed.)

    iPad models beginning in 2020 also feature the hardware microphone disconnect. When an MFI compliant case (including those sold by Apple) is attached to the iPad and closed, the microphone is disconnected in hardware, preventing microphone audio data being made available to any software—even with root or kernel privileges in iPadOS or in case the firmware is compromised.

    When Apple tries to lock stuff down, they don’t mess about.
    jony0dysamoria
  • Reply 10 of 13
    kschererkscherer Posts: 79member
    razorpit said:
    MplsP said:
    lkrupp said:
    Okay, so I  think I read way back that my iMac’s camera and indicator light were tied together and one could not activated without the other. Did I imagine that or am I right?
    I remember reading that, too. I found this thread discussing it that seems to say it may have been possible on the the older (i.e. > 10 years old) cameras but in the newer modules the LED is directly wired to the camera module's power supply.
    There should be an indicator like that for iOS devices.

    Does anyone know if this vulnerability was able to activate without turning on the LED on newer Macs?
    I haven't posted here for a while, but thought I would chime in on this. As others have said, newer Macs (I think 2012 and later, or somewhere thereabouts) have the camera and LED indicator wired together in a circuit. If memory serves, the camera draws power through the LED, so the camera cannot function unless the LED is functioning. They are a connected unit: If the light is on, the camera is on; if the camera is on, the light is on. It is not a software switch, but a hardware circuit. When you open an app through which camera access has been granted, electricity is passed through the LED (which turns it on) and then through the camera—it is one, single circuit. I am stating this based on a tech article I read about the subject some years ago, so my memory is a bit foggy regarding the specifics.
    dysamoria
  • Reply 11 of 13
    dysamoriadysamoria Posts: 3,430member
    So, Apple needs its own apps to not be granted permission automatically...
    cocoaken
  • Reply 13 of 13
    razorpit said:
    Just leave an indicator on for a little bit just like location services do. Go one step further, have one for the microphone too! That might surprise a lot of people.
    https://objective-see.com/products/oversight.html

    Superb, free (donation-ware).
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