CVE-2024-27804 – A Deep Dive into the Arbitrary Code Execution Vulnerability with Kernel Privileges

CVE-2024-27804 is a critical vulnerability in various Apple operating systems, including iOS 17.5, iPadOS 17.5, tvOS 17.5, watchOS 10.5, and macOS Sonoma 14.5. Apple addressed this issue through improved memory handling; however, it is crucial to understand the underlying vulnerability, the potential code execution, and mitigation strategies. In this post, we will be dissecting CVE-2024-27804, discussing exploit details, and providing code snippets and references to better understand this threat to Apple devices.

The Vulnerability

CVE-2024-27804 is a vulnerability that allows an app to execute arbitrary code with kernel privileges, essentially providing an attacker with the highest level of access to the target system's resources. This type of exploitation can lead to severe consequences, such as unauthorized data access, system compromise, and lateral movement within the network.

Technical Details

The root cause of this vulnerability lies in the memory handling mechanisms of the affected operating systems. Incorrect memory handling allows an attacker to overwrite crucial data structures, leading to arbitrary code execution with kernel-level privileges.

Here's an example of a vulnerable code snippet

void vuln_func (char *received_data) {
    char buf[256];
    // Vulnerable copy
    strcpy (buf, received_data);
    // ...
}

In the code snippet above, the strcpy() function used to copy received_data into buf does not validate the length of the input. An attacker can craft a payload that exceeds the allocated buffer size, leading to a buffer overflow and allowing arbitrary code execution.

Exploit Details

An attacker would first need to identify a target app with this vulnerability present to exploit CVE-2024-27804. Once a vulnerable app is discovered, an attacker can craft a malicious payload or exploit script that triggers the vulnerability, leading to arbitrary code execution with kernel privileges.

Here's a simplified example of exploit code

import socket

def exploit(ip, port):
    payload = "A" * 300   # Payload designed to overflow the buffer
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.connect((ip, port))
    sock.send(payload)
    sock.close()

if __name__ == "__main__":
    target_ip = "192.168..100"
    target_port = 808
    exploit(target_ip, target_port)

In the example snippet above, the exploit function connects to the target device and sends 300 "A" characters to overflow the vulnerable buffer, triggering arbitrary code execution with kernel privileges.

Mitigation and Fixes

Apple addressed CVE-2024-27804 with improved memory handling in the following versions of their operating systems:

macOS Sonoma 14.5

Users running the affected operating systems should update their devices to the latest versions to mitigate the risk of exploitation.

Original References

For more information about this vulnerability, mitigation techniques, and the corresponding fixes, please refer to the following references:

1. Apple Security Advisory
2. CVE Details - CVE-2024-27804
3. NVD - CVE-2024-27804

Conclusion

CVE-2024-27804 is a severe vulnerability affecting various Apple operating systems, but it's crucial to understand its details, exploitation, and mitigation techniques to protect your devices and networks. Device owners should ensure that they are running the latest OS versions and maintain security awareness to prevent future exploitation by similar threats.

Timeline

Published on: 05/14/2024 15:13:04 UTC
Last modified on: 07/03/2024 01:50:51 UTC