CVE-2026-20974 is a vulnerability classified under CWE-20 (Improper Input Validation) that affects Samsung Mobile devices prior to the SMR (Security Maintenance Release) January 2026 Release 1. The issue arises from improper validation of data related to network restrictions, specifically those enforcing Carrier Relock mechanisms. Carrier Relock is a security feature designed to restrict a mobile device to operate only on authorized carriers, preventing unauthorized unlocking and use on other networks. Due to improper input validation, a physical attacker with access to the device can bypass this Carrier Relock, effectively unlocking the device to operate on unauthorized carriers. The vulnerability does not require any authentication or user interaction, but physical access to the device is mandatory. The CVSS 4.0 vector indicates an attack vector of physical access (AV:P), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and no impact on confidentiality or availability (VC:N, VA:H, VI:H), with a medium overall score of 5.2. While no exploits are currently known in the wild and no patches have been officially released, the vulnerability poses a risk to device integrity and control over network usage. This flaw could be leveraged to circumvent carrier restrictions, potentially leading to unauthorized network access, billing fraud, or circumvention of carrier policies. The vulnerability affects Samsung Mobile devices broadly, though specific affected versions are not detailed. The issue was reserved in December 2025 and published in January 2026, indicating recent discovery and disclosure.

For European organizations, the primary impact of CVE-2026-20974 lies in the potential unauthorized unlocking of Samsung Mobile devices, which could lead to several operational and security concerns. Unauthorized carrier unlocking can result in devices being used on unapproved networks, complicating asset management and potentially violating carrier agreements. This could also facilitate fraudulent activities such as bypassing network restrictions or enabling unauthorized communication channels. While the vulnerability does not directly compromise data confidentiality or availability, it undermines device integrity and control, which could indirectly affect organizational security policies and compliance requirements. Organizations relying heavily on Samsung Mobile devices for secure communications or mobile workforce management may face increased risks of device misuse or loss of control over network access. Additionally, physical access requirements mean that insider threats or theft scenarios are the most likely exploitation vectors. The lack of known exploits reduces immediate risk but does not eliminate the need for vigilance. Overall, the impact is moderate but significant enough to warrant attention in environments where device control and carrier restrictions are critical.

To mitigate CVE-2026-20974, European organizations should implement a multi-layered approach beyond generic advice. First, enforce strict physical security controls to prevent unauthorized access to mobile devices, including secure storage and device tracking. Second, monitor Samsung’s official security advisories and promptly apply the SMR January 2026 Release 1 or subsequent patches addressing this vulnerability once available. Third, implement mobile device management (MDM) solutions that can detect and restrict unauthorized carrier unlocking attempts or unusual network behavior. Fourth, educate users about the risks of physical device compromise and encourage reporting of lost or stolen devices immediately. Fifth, consider deploying additional endpoint security controls that can alert on changes to device network configurations or SIM status. Finally, collaborate with mobile carriers to monitor for suspicious device activity that may indicate exploitation of this vulnerability. These targeted measures will help reduce the risk of exploitation and maintain control over mobile device network restrictions.