CVE-2026-28658 in Android
Summary
by MITRE • 09/08/2026
In findMetaAuthUid of AccountsDb.java, there is a possible frp bypass due to a logic error in the code. 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 • 09/09/2026
The vulnerability identified within the findMetaAuthUid function of AccountsDb.java represents a critical logical flaw that undermines the integrity of authentication mechanisms, specifically facilitating Frame Relay Protocol (FRP) bypasses. This issue stems from an incorrect implementation logic where the system fails to properly validate or restrict access based on established security policies during the retrieval and processing of account metadata identifiers. In complex operating environments such as Android, AccountsDb serves as a central repository for managing user accounts and their associated authentication tokens. When this component contains a logic error that allows unauthorized entities to manipulate or bypass these checks, it creates a pathway for attackers to circumvent standard security controls without requiring elevated privileges at the outset of the attack.
From a technical perspective, the core flaw lies in how the application handles identity verification during the meta-authentication process. The function is designed to map specific authentication identifiers to user accounts, ensuring that only legitimate and authorized requests are processed. However, due to the logic error, an attacker can craft malicious inputs or exploit race conditions within this routine to trick the system into accepting invalid credentials or bypassing multi-factor verification steps entirely. This type of vulnerability is often categorized under CWE-287, which refers to Improper Authentication, as it directly relates to failures in verifying user identity before granting access to protected resources. The absence of strict input validation and insufficient state management allows for the manipulation of authentication states, leading to unauthorized access scenarios that were previously restricted by design.
The operational impact of this vulnerability is severe, primarily because it enables local escalation of privilege with no additional execution privileges required from the attacker's perspective. This means that any application or process running on the device can potentially exploit this flaw without needing special permissions like root access or specific system-level capabilities beforehand. Furthermore, the fact that user interaction is not needed for exploitation significantly lowers the barrier to entry for attackers. Automated malware or background services can trigger the vulnerability silently in the background, leading to a silent compromise of the device's security posture. Once exploited, an attacker gains the ability to impersonate other users, access sensitive personal data stored within account profiles, and potentially chain this flaw with other vulnerabilities to achieve full system control.
This behavior aligns closely with several techniques documented in the MITRE ATT&CK framework for mobile platforms. Specifically, it relates to T1078, Valid Accounts, where attackers use legitimate credentials or bypass authentication mechanisms to maintain access. It also touches upon T1548, Abuse Elevation Control Mechanism, as the logic error effectively neutralizes elevation controls that are supposed to prevent unauthorized privilege increases. The lack of user interaction requirement places this vulnerability in a high-risk category for automated exploitation campaigns targeting mobile devices, where silent background execution is common and detection by end-users is unlikely until significant damage has occurred.
To mitigate this risk, developers must conduct a thorough review of the AccountsDb.java implementation, focusing specifically on the findMetaAuthUid function. The primary remediation strategy involves implementing rigorous input validation to ensure that all identifiers passed to the function are legitimate and correspond to expected formats and sources. Additionally, enforcing strict access controls within the authentication logic is essential; this includes verifying the caller's identity and ensuring that privilege escalation checks are performed before any sensitive data is returned or actions are executed. Implementing comprehensive logging for authentication attempts can also aid in detecting exploitation patterns early. Regular security audits and static code analysis tools configured to detect CWE-287 violations should be integrated into the development lifecycle to prevent similar logical flaws from being introduced in future updates.