A newfound vulnerability, dubbed CVE-2024-27856, has been identified in the processing of files within macOS Sonoma 14.5, iOS 16.7.8, and iPadOS 16.7.8. This vulnerability could potentially result in unexpected application termination or the execution of arbitrary code. The issue has been addressed through the implementation of improved checks, and is resolved in Safari 17.5, iOS 17.5, and iPadOS 17.5, watchOS 10.5, tvOS 17.5, and visionOS 1.2. This post will discuss the nature of the vulnerability, provide example code snippets, and supply original references to help users further understand and mitigate this security flaw.

Description of the Vulnerability

This vulnerability occurs when processing specific files, which can unexpectedly cause an application to terminate or enable the execution of arbitrary code within the system. The root of the issue stems from improper validation of user-supplied input, allowing potential attackers to exploit the security gaps and maliciously manipulate the system. To address this issue, developers have implemented improved checks on the latest macOS Sonoma, iOS, and iPadOS versions.

Here's an example of a code snippet that demonstrates the vulnerability

#import <Foundation/Foundation.h>

int main(int argc, char * argv[]) {
    @autoreleasepool {
        // Incorrect data validation
        NSString *input = argv[1];
        if (input.length < 10) {
            // Execute the dangerous code
            NSLog(@"this could crash or allow for arbitrary code execution");
        }
    }
    return ;
}

The malicious file may look like this

{
    "type": "DEMO_EXPLOIT",
    "content": "<malicious_code_here>"
}

1. CVE-2024-27856 – NVD Detail
2. Apple security updates

Exploit Details

To exploit this vulnerability, an attacker would typically create a file with crafted content designed to exploit the inadequate input validation, as seen in the example provided. This file would then need to be processed by the affected application, leading to potential disturbances in system functionality or, in worse case scenarios, arbitrary code execution.

Mitigation and Patching

It is highly recommended that users of macOS Sonoma 14.5, iOS 16.7.8, and iPadOS 16.7.8 update their systems to the latest available versions (currently Safari 17.5, iOS 17.5, and iPadOS 17.5). Additionally, watchOS 10.5, tvOS 17.5, and visionOS 1.2 versions should be updated to ensure system security.

Developers can utilize the updated input validation introduced in newer OS versions that include improved checks. This security measure prevents the potential abuse of malformed files to compromise the system.

By implementing these improvements and maintaining updated systems, users and developers can counteract the risks associated with CVE-2024-27856 and safeguard their applications and devices.

Timeline

Published on: 01/15/2025 20:15:27 UTC
Last modified on: 03/14/2025 13:42:15 UTC