CVE-2022-39900 is an improper access control vulnerability (CWE-284) identified in Samsung Mobile Devices, specifically affecting the Nice Catch application prior to the SMR (Security Maintenance Release) December 2022 Release 1. Nice Catch is a diagnostic tool pre-installed on Samsung devices that logs various system events, including toast messages, which are brief notifications displayed by applications. The vulnerability allows a physical attacker with access to the device to retrieve the contents of all toast messages generated by applications installed within the Secure Folder environment. The Secure Folder is a Samsung security feature that creates a separate, encrypted space on the device to isolate sensitive apps and data. Normally, this environment is designed to prevent unauthorized access to its contents, including notifications. However, due to improper access control in Nice Catch, toast messages from Secure Folder apps are exposed and accessible to an attacker who can physically interact with the device. The affected Samsung device versions include Android releases R (11), S (12), and T (13), indicating a wide range of devices are vulnerable if not updated. No known exploits have been reported in the wild, and Samsung has not yet provided direct patch links, but the issue is acknowledged and classified as medium severity. The vulnerability does not require remote exploitation or network access; it requires physical access to the device, which limits the attack vector but still poses a significant risk to confidentiality of sensitive information displayed in toast messages within the Secure Folder. This could include sensitive notifications such as authentication codes, personal messages, or other confidential data that apps display via toast notifications.

For European organizations, especially those handling sensitive or regulated data on Samsung mobile devices, this vulnerability poses a confidentiality risk. If an attacker gains physical access to an employee's device, they could extract sensitive information from Secure Folder apps, potentially leading to data leakage or unauthorized disclosure of corporate secrets, personal data, or authentication tokens. This is particularly concerning for sectors like finance, healthcare, legal, and government agencies where Secure Folder is used to protect sensitive apps and data. Although the vulnerability does not allow remote exploitation, the risk of insider threats, device theft, or loss is non-negligible. The integrity and availability of data are not directly impacted by this vulnerability, but the breach of confidentiality could lead to further attacks or social engineering. The medium severity rating reflects the limited attack vector but significant confidentiality impact. Organizations relying on Samsung devices for secure mobile workflows should consider this vulnerability in their risk assessments and mobile device management policies.

1. Immediate mitigation involves updating Samsung devices to the latest Security Maintenance Release (SMR) December 2022 Release 1 or later, where this vulnerability is addressed. 2. Enforce strict physical security policies for mobile devices, including mandatory device locking, use of biometric authentication, and employee training on device loss prevention. 3. Limit the use of toast notifications for sensitive information within Secure Folder apps; developers should avoid displaying confidential data in toast messages. 4. Employ Mobile Device Management (MDM) solutions to monitor device compliance and remotely wipe devices if lost or stolen. 5. Audit and restrict access to diagnostic tools like Nice Catch where possible, or disable them if not required for business operations. 6. Implement endpoint detection and response (EDR) solutions that can alert on unusual physical access or diagnostic tool usage. 7. Encourage users to report lost or stolen devices immediately to enable rapid incident response. These steps go beyond generic advice by focusing on controlling physical access, minimizing sensitive data exposure in UI elements, and leveraging enterprise controls to reduce risk.