CVE-2022-20176 in Android
Summary
by MITRE • 06/15/2022
In auth_store of sjtag-driver.c, there is a possible read of uninitialized memory due to a missing bounds check. This could lead to local information disclosure with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-197787879References: N/A
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Analysis
by VulDB Data Team • 06/15/2022
The vulnerability identified as CVE-2022-20176 resides within the authentication storage component of the sjtag-driver.c file in the Android kernel ecosystem. This flaw represents a critical security weakness that stems from inadequate input validation mechanisms within the kernel-level driver responsible for managing secure authentication data. The vulnerability manifests as a potential read of uninitialized memory, a condition that can occur when the system attempts to access memory locations that have not been properly initialized or validated before use.
The technical root cause of this vulnerability lies in the absence of proper bounds checking within the auth_store function. When processing authentication data, the driver fails to validate the size or boundaries of incoming data structures before attempting to read from memory locations. This missing validation creates an exploitable condition where uninitialized memory contents may be inadvertently exposed to unauthorized processes. The vulnerability specifically affects the sjtag driver which is typically used for secure debugging and authentication operations within Android devices, making it particularly concerning for system integrity.
From an operational perspective, this vulnerability presents a significant risk for local information disclosure attacks. An attacker with system execution privileges can leverage this flaw to extract sensitive data from uninitialized memory regions that may contain previously used authentication tokens, cryptographic keys, or other confidential information. The attack requires only local system execution privileges, eliminating the need for complex network-based exploitation or user interaction, which makes it particularly dangerous in environments where privilege escalation is possible. The Android kernel's tight integration with system-level operations means that successful exploitation could lead to broader compromise of the device's security posture.
The impact of this vulnerability extends beyond simple information disclosure, as it represents a potential pathway for more sophisticated attacks within the Android security model. The uninitialized memory read condition can expose sensitive data that may include authentication credentials, session tokens, or cryptographic material that could be leveraged for further exploitation. This vulnerability aligns with CWE-457, which specifically addresses the use of uninitialized variables, and demonstrates how such conditions can lead to information disclosure in kernel-level components. The ATT&CK framework categorizes this as a privilege escalation technique where local system access can be leveraged to extract confidential information from memory.
Mitigation strategies for CVE-2022-20176 should focus on implementing comprehensive bounds checking within the auth_store function and ensuring proper initialization of all memory regions before data access operations. Android kernel developers should implement input validation mechanisms that verify data boundaries and sizes before processing authentication information. Regular security audits of kernel drivers should include thorough review of memory access patterns and validation procedures. Additionally, system administrators should ensure that Android devices are updated with patches that address this specific vulnerability, as the fix typically involves adding proper bounds checking and memory initialization routines to prevent uninitialized memory reads. The vulnerability underscores the importance of rigorous code review processes for kernel-level components and highlights the critical need for comprehensive testing of security-sensitive functions.