CVE-2025-20936
CVE-2025-20936: Improper Access Control in HDCP Trustlet
Description:
Improper access control in the HDCP trustlet within Samsung devices prior to the SMR Apr-2025 Release 1 allows a local attacker with shell privilege to escalate their privileges to root. This vulnerability stems from insufficient restriction on access to sensitive HDCP trustlet functionalities.
Severity:
- CVSS v3.1 Score: 8.8 (High)
- CVSS Vector: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Known Exploit:
While specific exploit code is not provided, the vulnerability allows privilege escalation to root from a local shell. An attacker with shell access can leverage this flaw to execute arbitrary code with root privileges. The exploitation would likely involve crafting a malicious request or command that bypasses the inadequate access controls and allows unauthorized interaction with the HDCP trustlet.
Remediation/Mitigation Strategy:
Apply Security Patch:
- Primary Mitigation: Upgrade Samsung devices to the SMR Apr-2025 Release 1 (or later) to incorporate the fix for this vulnerability. This patch addresses the improper access control within the HDCP trustlet.
- Verification: After applying the patch, verify that the HDCP trustlet’s access controls are correctly implemented and prevent unauthorized access.
Restrict Shell Access:
- Mitigation: Minimize and restrict access to the local shell on Samsung devices. Employ strong authentication mechanisms and limit shell access only to authorized personnel.
- Rationale: Reducing the number of users with shell access lowers the attack surface for this vulnerability.
Implement Principle of Least Privilege:
- Mitigation: Enforce the principle of least privilege for all applications and processes running on the device. Ensure that applications only have the necessary permissions to perform their intended functions.
- Rationale: This limits the potential damage that can be caused by an attacker who has gained initial access.
Monitor System Activity:
- Mitigation: Implement robust monitoring and logging of system activity, including access to sensitive components like the HDCP trustlet.
- Rationale: This can help detect and respond to potential exploitation attempts. Pay attention to unexpected or unauthorized access patterns.
User Education:
- Mitigation: Educate users about the importance of not installing applications from untrusted sources and the risks associated with granting excessive permissions to applications.
- Rationale: While not a direct fix for the HDCP trustlet, user awareness can reduce the likelihood of malicious applications gaining initial access to the device, which could be a prerequisite for exploiting this vulnerability.
Long-Term Strategy:
- Secure Development Practices: Implement secure development practices to ensure that access control mechanisms are properly implemented and validated during the development process. This includes regular security audits and penetration testing of sensitive components.
- Automated Vulnerability Scanning: Integrate automated vulnerability scanning into the development pipeline to identify and address potential security vulnerabilities early in the development lifecycle.
- Security Hardening: Implement security hardening measures to reduce the overall attack surface of the device. This may include disabling unnecessary services and restricting access to sensitive resources.
Assigner
- Samsung Mobile [email protected]
Date
- Published Date: 2025-04-08 05:15:38
- Updated Date: 2025-04-08 18:13:53