CVE-2026-58726 in Android
Summary
by MITRE • 09/15/2026
In FsmReleaseKey of fsm.c, there is a possible permission bypass due to a missing permission check. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability identified in the FsmReleaseKey function within fsm.c represents a critical security flaw rooted in insufficient access control mechanisms. Specifically, this issue manifests as a missing permission check during the release or revocation of file system keys. In operating systems and kernel-level components, such functions are responsible for managing references to cryptographic material or secure storage handles that protect sensitive data structures. When an application or process invokes FsmReleaseKey without verifying whether it possesses the necessary privileges to perform this action, the integrity of the access control model is compromised. This absence of validation allows any authenticated user, regardless of their privilege level, to interact with resources they should not be able to modify or release. The core technical flaw lies in the failure of the function to validate the current security context against a predefined set of allowed permissions before proceeding with the key release operation.
From an operational perspective, this vulnerability facilitates local escalation of privilege. Because the missing check does not require user interaction for exploitation, an attacker can craft a malicious application or script that repeatedly calls FsmReleaseKey on protected keys associated with higher-privilege processes or system components. By successfully releasing these keys without authorization, the attacker may gain unauthorized access to sensitive data structures, potentially leading to full control over the affected subsystem. The requirement of System execution privileges for successful exploitation indicates that while the initial entry point is accessible to lower-privileged users, the ultimate impact targets high-value assets typically protected by elevated permissions. This dynamic allows a low-privilege user to indirectly manipulate system-level resources, effectively bypassing standard security boundaries and achieving code execution or data exfiltration with System-level authority.
This vulnerability aligns closely with Common Weakness Enumeration (CWE) category CWE-269, which describes Improper Privilege Management. The specific nature of the flaw also correlates with CWE-732, as it involves incorrect assignment of permissions to critical system functions. In terms of offensive security frameworks, this behavior is consistent with techniques found in the MITRE ATT&CK catalog under Local Privilege Escalation (T1068). Attackers often leverage such flaws to transition from a standard user context to an administrator or SYSTEM account, which serves as a foundational step for further lateral movement and persistence within a compromised network. The lack of mandatory access control enforcement in this specific code path highlights a gap in the defense-in-depth strategy, allowing attackers to bypass intended security restrictions through simple API misuse rather than complex exploitation chains involving memory corruption or race conditions.
Mitigation strategies must focus on enforcing strict validation at the point of entry for all sensitive operations. Developers should implement comprehensive permission checks within FsmReleaseKey prior to executing any logic related to key release. This involves verifying that the calling process holds specific privileges, such as SE_SECURITY_NAME or equivalent administrative rights, depending on the operating system's security model. Additionally, implementing principle of least privilege ensures that even if a vulnerability exists in one component, its impact is contained by restricting what lower-privileged users can access. Regular code audits focusing on authentication and authorization logic are essential to identify similar gaps across other functions. Furthermore, adopting static analysis tools configured with rules for CWE-269 can help detect these omissions during the development lifecycle. For deployed systems, applying vendor-provided patches that address this specific flaw is critical, as runtime mitigations like Address Space Layout Randomization or Data Execution Prevention do not directly prevent logic-based privilege escalation vulnerabilities of this nature.