CVE-2022-32926 - How an Apple Kernel Vulnerability Allowed Root Apps to Gain Kernel Privileges (with Code Example and Patch Details)

In October 2022, Apple quietly pushed out patches for one of its more serious security vulnerabilities, tracked as CVE-2022-32926. The issue was found across a wide range of devices including iPhones, iPads, Macs, Apple TVs, and Apple Watches. It allowed a privileged app—that already had “root”—to execute arbitrary code at the kernel level, in effect taking over the whole device at the deepest level.

In this article, we’ll explore what this vulnerability was, how it worked, why it mattered, and show a simplified code example to help explain the concept. This post is original, written in straightforward language for techies and learners alike.

What Was CVE-2022-32926?

CVE-2022-32926 was a vulnerability in Apple’s kernel, the core part of the operating system that controls everything on the device. The official Apple security notes described it like this:

> "The issue was addressed with improved bounds checks. An app with root privileges may be able to execute arbitrary code with kernel privileges."
> — Apple Security Updates

In plain English: if you had an app running as root (already pretty powerful), a bug in the kernel’s bounds checking could let that app run code inside the kernel itself. Kernel code has total control of memory, hardware, and security. This is the difference between being a landlord and being the mayor.

Technical Explanation (What Went Wrong)

The vulnerability was a “bounds check” bug. Many kernel components handle arrays or buffers—chunks of memory that can be filled with data. "Bounds checking" is making sure you don't read or write past the end of a buffer. If you mess this up, bad things can happen.

In this case, Apple was not properly checking that values passed into the kernel were within expected limits. That meant a root-level app could trick the system into reading or writing to memory where it wasn’t supposed to. When you can overwrite the right memory in the kernel, you can often inject and execute your own code.

Simplified Code Example

Here’s a made-up but similar example of what can go wrong with bad bounds checks in C, the language much of the Apple kernel uses:

// Vulnerable function
void process_buffer(int index, int *buffer) {
    int value;
    // BAD: No check on index bounds
    value = buffer[index];
    // ...do something with value...
}

A safe version should check if 'index' is within the accepted range

// Fixed function
void process_buffer(int index, int *buffer, int buf_len) {
    int value;
    if (index >=  && index < buf_len) {
        value = buffer[index];
        // ...do something with value...
    } else {
        // Handle error
    }
}

What this means: The “improved bounds checks” in Apple’s patch make sure user-provided values can’t trick the kernel into reading or writing illegal memory.

watchOS before 9.1

> Reference: Apple Support CVE-2022-32926 Advisory

How Could This Be Exploited?

Anyone with a root-level app could target this bug. Most Apple users don't have root access, but jailbreakers or anyone targeted by malware taking advantage of another root-exploit could “chain” this bug for full device compromise.

2. The code crafts a request to the vulnerable kernel function, using a bad index or pointer to escape bounds.

Code runs at kernel level—now, the attacker can do anything, even disable security protections.

Here’s a very basic, “pseudo-code” exploit without specifics (as giving a real exploit here would be unethical):

// Pseudo-exploit targeting bad bounds check
int malicious_index = 10000; // Intentionally out-of-bounds index
trigger_vulnerable_kernel_function(malicious_index, my_data);

With a working chain, attackers would now have total device control.

When and How Did Apple Fix It?

Apple fixed CVE-2022-32926 with something simple and classic: improved bounds checks. This means Apple added proper checks in the code to make sure any incoming value was restricted to valid ranges, stopping the kind of memory corruption possible before.

iOS 16.1 and iPadOS 16

> For the official advisory, see:
> https://support.apple.com/en-us/HT213489

Why Is This a Big Deal?

- Kernel-level exploits are catastrophic: Once an attacker is in the kernel, basically all security is out the window.
- Chaining vulnerabilities: Even if not exploitable directly by a regular app, attackers often chain together multiple vulnerabilities.
- Apple’s secrecy: Apple only released bare details, as is typical, so the bug would not be widely exploited “in the wild.”

What Should You Do?

Update all your Apple devices—especially if you use older supported hardware. Stay off jailbroken devices, and avoid installing suspicious apps that ask for more permissions than necessary.

Summary

CVE-2022-32926 exposed a powerful flaw in Apple’s foundation, giving root apps a hidden doorway to seize total control. Apple’s quick improvement of its bounds checks shut that door, but this event reminds us how even tiny coding oversights can have giant consequences.

Bottom line: Update now—kernel bugs are no joke, and Apple has already patched this one.

*Written for security learners and Apple watchers. Do not attempt to exploit or misuse vulnerabilities. Stay safe and stay updated!*

Timeline

Published on: 11/01/2022 20:15:00 UTC
Last modified on: 11/02/2022 17:42:00 UTC