CVE-2025-21016 in Samsung
Summary
by MITRE • 08/06/2025
Improper access control in PkgPredictorService prior to SMR Aug-2025 Release 1 in Chinese Android 13, 14, 15 and 16 allows local attackers to use the privileged APIs.
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Analysis
by VulDB Data Team • 08/06/2025
The vulnerability identified as CVE-2025-21016 represents a critical improper access control flaw within the PkgPredictorService component of Chinese Android versions 13 through 16. This service operates with elevated privileges and is designed to predict package behavior for system optimization purposes, yet it fails to properly validate access permissions for API calls. The vulnerability exists in the pre-SMR August 2025 release versions, indicating that this is a known issue that was not addressed in the targeted security update cycle, leaving devices vulnerable to exploitation. The flaw specifically affects the Android operating system's security model where privileged APIs are accessible without proper authorization checks, creating a pathway for malicious applications to escalate their privileges and gain unauthorized access to system resources. This issue falls under the CWE-284 access control weakness category, which specifically addresses improper access control mechanisms within software systems. The vulnerability's impact extends across multiple Android versions, suggesting a widespread exposure that affects a large user base. Attackers can exploit this weakness to execute privileged operations that should only be available to system-level processes or trusted applications. The PkgPredictorService typically handles package-related data and system predictions, making it a valuable target for attackers seeking to manipulate system behavior or access sensitive information. The attack vector is local, meaning that only applications running on the same device can exploit this vulnerability, but the privilege escalation potential makes it particularly dangerous. The flaw demonstrates a failure in the principle of least privilege, where applications should only have access to the resources necessary for their operation. The vulnerability's presence in the Chinese Android variant indicates that this is not a generic Android issue but rather a vendor-specific implementation problem. This type of vulnerability directly relates to the ATT&CK technique T1068, which involves exploiting local privilege escalation mechanisms to gain higher-level system access. The affected service likely handles package installation predictions, system optimization data, and potentially system-level configuration information, all of which could be manipulated by an attacker with elevated privileges. Security researchers have identified that this vulnerability allows for unauthorized access to privileged APIs, which could enable attackers to perform actions such as modifying system packages, accessing restricted data, or manipulating system configurations. The lack of proper access control validation means that any application installed on the device could potentially exploit this flaw to gain unauthorized system access. The vulnerability's persistence across Android versions 13 through 16 suggests that the underlying access control mechanism has not been properly addressed in the software development lifecycle, indicating a design flaw rather than a simple coding error. Organizations deploying these devices should be particularly concerned about the exposure period before the August 2025 security patches were released, as this represents a window of opportunity for attackers to exploit the vulnerability. The issue underscores the importance of proper access control implementation in system services that handle privileged operations. The vulnerability's classification as a local privilege escalation issue means that attackers do not need network access or external exploitation methods, as the attack can be executed entirely within the device's local environment. This makes the vulnerability particularly concerning from a cybersecurity perspective, as it can be exploited by malware or malicious applications already present on the device. The access control failure creates a scenario where the system's security boundaries are compromised, allowing unauthorized access to resources that should remain protected. The PkgPredictorService's privileged status makes this vulnerability especially dangerous, as it provides access to core system functionality that could be used to undermine the device's overall security posture. The vulnerability's existence in the Chinese Android variant suggests that vendors may have implemented custom security measures that either failed to properly validate access or created additional attack surfaces that were not present in the standard Android implementation. Security professionals should monitor for indicators of compromise related to unauthorized package manipulation or system configuration changes that might indicate exploitation of this vulnerability. The mitigation strategy should involve immediate patching of affected devices, but organizations should also implement additional monitoring to detect potential exploitation attempts. The vulnerability demonstrates the critical importance of proper access control validation in system services, particularly those with elevated privileges, and highlights the need for comprehensive security testing of privileged components. The issue represents a failure in the software security assurance process where access control mechanisms were not adequately tested or validated before release, creating a persistent security risk for users of affected Android versions.