CVE-2025-24118 - Understanding and Exploiting the macOS/iPadOS Kernel Memory Vulnerability

In June 2025, Apple patched an important kernel vulnerability known as CVE-2025-24118. This flaw affected major Apple platforms and could let an app crash the system or even write into kernel memory—opening doors to much more dangerous attacks. Let's break down how this bug worked, see the affected systems, look at public exploit ideas, and see code snippets along the way. I’ll also share links to the original Apple advisory and resources if you want to read further.

Apple described this issue as follows

> "The issue was addressed with improved memory handling. This issue is fixed in iPadOS 17.7.4, macOS Sequoia 15.3, macOS Sonoma 14.7.3. An app may be able to cause unexpected system termination or write kernel memory."
>
> Source: Apple Security Updates

In simple words, this means a flaw in how the operating system managed memory could let a malicious app interact with the kernel in unsafe ways. Usually, only highly trusted code should have that power.

macOS Sonoma versions before 14.7.3

If you’re not already running one of the fixed versions, update as soon as possible.

How Does the Exploit Work?

While Apple did not disclose very specific technical details, security researchers have analyzed patterns in these sorts of kernel bugs. Typically, the issue comes from a memory mismanagement in a kernel API accessible from userland—often a malformed system call or an abused device driver.

Here’s how attackers often approach this

1. Find a system call or interface exposed to userland apps that does not properly check buffer sizes or pointer validity.

Craft a payload that causes an out-of-bounds write or use-after-free in kernel memory.

3. Exploit this memory corruption to either crash the system (a DoS) or escalate privileges (if writable kernel memory is achieved).

Example Exploit: Writing to Kernel Memory (Hypothetical)

Below is a *simplified illustrative* code snippet, showing how an attacker could trigger a kernel panic or write in kernel space if such a bug was accessible via an IOConnectCallMethod (common with IOKit vulnerabilities):

#include <stdio.h>
#include <IOKit/IOKitLib.h>

int main() {
    // Open a connection to a vulnerable kernel service
    io_service_t service = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("AppleVulnerableService"));
    if (!service) {
        printf("Service not found.\n");
        return -1;
    }

    io_connect_t connect = ;
    kern_return_t kr = IOServiceOpen(service, mach_task_self(), , &connect);
    IOObjectRelease(service);
    if (kr != KERN_SUCCESS) {
        printf("Failed to open service.\n");
        return -1;
    }

    // Malformed input that triggers out-of-bounds write
    uint64_t inputScalar[16] = {};
    size_t inputScalarCnt = 16; // intentionally large
    uint8_t inputStruct[x100];
    size_t inputStructCnt = x100;

    kr = IOConnectCallMethod(connect, , inputScalar, inputScalarCnt, inputStruct, inputStructCnt, NULL, NULL, NULL, NULL);

    if (kr != KERN_SUCCESS) {
        printf("Method call failed. System stability may be affected!\n");
    }
    IOServiceClose(connect);
    return ;
}

If exploited, this vulnerability could allow a regular user-level app to

- Crash the entire Mac or iPad (Denial-of-Service/DoS)
- Write to arbitrary kernel memory (leading to privilege escalation, code injection, or disabling security protections)

For attackers, this means getting kernel-level access, bypassing most protections (System Integrity Protection, SIP), and potentially compromising the whole device.

Affected users should upgrade to

- iPadOS 17.7.4 or later (iPadOS Update Instructions)
- macOS Sequoia 15.3 or later (macOS Update Instructions)

Timeline

Published on: 01/27/2025 22:15:17 UTC
Last modified on: 01/28/2025 16:15:42 UTC