CVE-2023-21388 in Android
Summary
by MITRE • 10/30/2023
In Settings, there is a possible restriction bypass due to a missing permission check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 11/22/2023
The vulnerability identified as CVE-2023-21388 resides within the Settings application component of a mobile operating system, representing a critical privilege escalation flaw that undermines the system's security model. This issue manifests as a missing permission check that allows unauthorized processes to bypass normal access controls and elevate their privileges to system level. The vulnerability specifically affects the permission enforcement mechanisms within the settings framework, where proper authorization validation fails to occur during critical operations. According to CWE-284, this represents an inadequate permission check or access control mechanism that directly enables unauthorized privilege escalation. The flaw operates at the system level where applications or processes that should be restricted from accessing certain settings or system resources can exploit this gap to gain elevated privileges without requiring any additional malicious code execution or user interaction.
The technical implementation of this vulnerability stems from the absence of proper access control validation within the settings subsystem. When a process attempts to modify or access restricted settings, the system should verify that the requesting entity possesses the necessary permissions before granting access. However, in this case, the permission checking logic fails to properly validate the requesting process's credentials or identity, allowing malicious actors to manipulate system settings that should be restricted to privileged applications or system components. The lack of proper permission validation creates a direct path for privilege escalation, as demonstrated by the ATT&CK technique T1068 which describes the exploitation of legitimate credentials and privileges to gain unauthorized access to system resources. This flaw essentially creates a backdoor within the system's own permission enforcement mechanisms, allowing processes to bypass normal security boundaries and operate with elevated privileges.
The operational impact of CVE-2023-21388 is severe and potentially catastrophic for system security. An attacker who can exploit this vulnerability gains the ability to escalate privileges locally without requiring any additional malicious payloads or user interaction, making the exploit highly reliable and dangerous. The vulnerability essentially allows any process to bypass system restrictions and gain access to system-level functionalities that should be protected from unauthorized access. This could enable attackers to modify critical system settings, disable security features, access sensitive data, or install malicious components with elevated privileges. The lack of user interaction requirement significantly increases the exploitability factor, as it allows for automated exploitation without the need for social engineering or user deception. The vulnerability directly violates fundamental security principles of least privilege and separation of concerns, potentially allowing complete system compromise through a single attack vector.
Mitigation strategies for CVE-2023-21388 must address the root cause of the missing permission check through comprehensive system hardening and access control reinforcement. The most effective approach involves implementing proper authorization validation mechanisms within the settings subsystem, ensuring that all access attempts to restricted system resources undergo rigorous permission verification before granting access. System administrators should apply the latest security patches and updates provided by the vendor to remediate this vulnerability, as the fix typically involves restoring proper permission checking logic within the affected components. Organizations should also implement monitoring solutions to detect unauthorized access attempts to system settings and privilege escalation activities. The vulnerability highlights the importance of proper input validation and access control implementation, as outlined in the OWASP Top Ten security principles, particularly focusing on the prevention of privilege escalation attacks. Additionally, security teams should conduct regular audits of system permission models and access controls to identify and remediate similar weaknesses that could potentially allow unauthorized privilege escalation through different attack vectors.