CVE-2022-42543 in Android
Summary
by MITRE • 12/16/2022
In fdt_path_offset_namelen of fdt_ro.c, there is a possible out of bounds read due to an incorrect 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-249998113References: N/A
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Analysis
by VulDB Data Team • 04/17/2025
The vulnerability identified as CVE-2022-42543 resides within the flattened device tree (FDT) implementation of the Android kernel, specifically in the fdt_path_offset_namelen function located in fdt_ro.c. This flaw represents a critical out-of-bounds read condition that arises from an inadequate bounds checking mechanism during device tree traversal operations. The vulnerability manifests when the kernel processes device tree data structures that are typically used to describe hardware configuration to the operating system. The incorrect bounds check allows an attacker to manipulate input data in such a way that memory locations outside the intended buffer boundaries are accessed, potentially exposing sensitive kernel memory contents to unauthorized parties.
The technical nature of this vulnerability aligns with CWE-129, which describes improper validation of array indices, and specifically relates to improper bounds checking in kernel space memory operations. The flaw occurs during the processing of device tree paths where the function fails to properly validate the length of path components against available buffer space. This type of vulnerability falls under the ATT&CK technique T1068, which involves exploiting legitimate credentials and system privileges to gain access to sensitive system information. The vulnerability requires system execution privileges for exploitation, indicating that an attacker must already have elevated access to the system to leverage this flaw effectively.
The operational impact of CVE-2022-42543 extends beyond simple information disclosure, as it can potentially expose kernel memory contents that may contain sensitive data such as cryptographic keys, memory addresses, or other confidential information. The local information disclosure aspect means that an attacker with system-level privileges can access memory regions that should remain protected, potentially leading to further exploitation opportunities. This vulnerability is particularly concerning in Android environments where device tree data is used extensively for hardware abstraction and system configuration management. The Android ID A-249998113 indicates this was tracked within Google's internal vulnerability management system, highlighting its significance in the Android ecosystem.
Mitigation strategies for this vulnerability involve applying the relevant kernel patches provided by Android security teams and ensuring that all device tree data is properly validated before processing. System administrators should prioritize updating kernel versions to include the patched implementation of fdt_path_offset_namelen function, which corrects the bounds checking logic. Additionally, implementing proper input validation mechanisms for device tree data and employing memory safety techniques such as address sanitization can help prevent similar issues in the future. The vulnerability demonstrates the importance of rigorous bounds checking in kernel space operations and underscores the need for comprehensive security testing of core system components that handle critical hardware abstraction data structures.