In recent weeks, a new security vulnerability has been identified and assigned a CVE identifier: CVE-2022-39885. This vulnerability has been found within the BootCompletedReceiver_CMCC component that exists in the DeviceManagement software used in various devices. This post aims to provide a detailed analysis of this vulnerability along with a code snippet and original references. The focus here is to highlight the exploitable nature of this vulnerability in the hands of a local attacker, and how it can lead to unauthorized access to sensitive device information.

Background

BootCompletedReceiver_CMCC resides in the DeviceManagement software and is responsible for ensuring the proper initialization of the device after the boot process is completed. Unfortunately, as discovered in CVE-2022-39885, this component contains an improper access control vulnerability that enables a local attacker to breach and retrieve sensitive device information without needed authorization. Consequently, the severity of this vulnerability has drawn attention from the security community, as it can lead to the compromise of legitimate users' data.

Code Snippet

The following code snippet is an example of how the vulnerable code may look within the BootCompletedReceiver_CMCC class:

class BootCompletedReceiver_CMCC extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        if (Intent.ACTION_BOOT_COMPLETED.equals(intent.getAction())) {
            // Retrieve sensitive device information
            String deviceInfo = getDeviceInfo(context);

            // Perform actions based on retrieved information
            storeDeviceInfo(context, deviceInfo);
        }
    }

    private String getDeviceInfo(Context context) {
        // Code for retrieving sensitive device information
    }

    private void storeDeviceInfo(Context context, String deviceInfo) {
        // Code for storing retrieved information and possible vulnerable access control
    }
}

Exploit Details

The exploit allowing unauthorized access to device information starts with the local attacker sending a malicious BOOT_COMPLETED broadcast intent. Since the BootCompletedReceiver_CMCC is missing proper access control mechanisms, it will accept and process this intent, thus granting unintended access to sensitive device information like IMEI, phone number, and device ID.

In turn, the attacker can obtain this information and then leverage it for malicious purposes such as tracking a user's location, performing identity theft or even accessing other sensitive accounts.

Original References

For more information about the vulnerability as well as the suggested remediation measures, refer to the following original sources:

1. CVE-2022-39885 at NVD (National Vulnerability Database)
2. Advisory for SMR-Nov-2022 Release 1

Mitigation

In order to mitigate the risks associated with CVE-2022-39885, it is essential that all affected devices be updated to the SMR Nov-2022 Release 1 or later as soon as possible. This release provides the necessary patches to address the improper access control vulnerability present in the BootCompletedReceiver_CMCC component, thus rendering it resistant to potential malicious exploitation.

Conclusion

CVE-2022-39885 is a significant security vulnerability that has the potential to compromise the sensitive information of countless device users. Understanding the specifics of this vulnerability, its implications, and the mitigation steps required can help ensure the highest level of security and privacy for users. As a responsible device owner, it is vital to maintain awareness of such threats and take timely action to prevent potential breaches and unauthorized access to personal information.

Timeline

Published on: 11/09/2022 22:15:00 UTC
Last modified on: 11/10/2022 15:22:00 UTC