CVE-2025-20987 is a medium-severity vulnerability affecting Samsung Mobile Devices, specifically related to improper access control in the fingerprint trustlet component prior to the SMR (Security Maintenance Release) May-2025 Release 1. The fingerprint trustlet is a trusted execution environment (TEE) component responsible for handling biometric authentication data securely. This vulnerability allows a local attacker with privileged access to the device to obtain an authentication token (auth_token) improperly. The auth_token is a sensitive piece of information that can be used to bypass biometric authentication mechanisms or escalate privileges further within the device. The CVSS 3.1 base score is 5.2, reflecting a medium impact with the following vector: Attack Vector (AV:L) - local access required; Attack Complexity (AC:H) - high complexity; Privileges Required (PR:H) - high privileges needed; User Interaction (UI:N) - none required; Scope (S:U) - unchanged; Confidentiality (C:H) - high impact; Integrity (I:L) - low impact; Availability (A:L) - low impact. The vulnerability does not require user interaction but does require the attacker to have local privileged access, which limits the attack surface to scenarios where an attacker has already compromised the device or has physical access and can escalate privileges. There are no known exploits in the wild at the time of publication, and no patch links have been provided yet. The vulnerability falls under CWE-200, indicating exposure of sensitive information to unauthorized actors due to improper access control mechanisms in the fingerprint trustlet.

For European organizations, this vulnerability poses a significant risk primarily to employees and executives using Samsung Mobile Devices for sensitive communications and access to corporate resources. If an attacker gains local privileged access—potentially through malware, physical device compromise, or insider threats—they could extract authentication tokens that bypass biometric security, enabling unauthorized access to corporate applications, emails, and confidential data. This could lead to data breaches, intellectual property theft, or unauthorized transactions. The impact is heightened in sectors with strict data protection requirements such as finance, healthcare, and government agencies. Additionally, the exposure of biometric authentication tokens undermines user trust in device security and could facilitate further lateral movement within corporate networks. However, the requirement for local privileged access and the high attack complexity reduce the likelihood of widespread exploitation, limiting the threat mainly to targeted attacks or insider threats.

European organizations should implement a multi-layered mitigation strategy beyond generic patching advice: 1) Enforce strict device management policies using Mobile Device Management (MDM) solutions to restrict installation of unauthorized applications and monitor for privilege escalation attempts. 2) Employ endpoint detection and response (EDR) tools on mobile devices to detect suspicious local privilege escalation activities. 3) Educate users on the risks of physical device compromise and enforce strong device lock mechanisms including PINs and passwords in addition to biometrics. 4) Limit the use of Samsung Mobile Devices for highly sensitive operations until the vendor releases a security patch. 5) Monitor for unusual authentication token usage or anomalies in biometric authentication logs if available. 6) Segregate sensitive applications and data using containerization or secure work profiles to reduce the impact of a compromised device. 7) Coordinate with Samsung for timely updates and apply the SMR May-2025 Release 1 or later as soon as it becomes available to remediate the vulnerability.