CVE-2018-11903 in Android
Summary
by MITRE
In all android releases (Android for MSM, Firefox OS for MSM, QRD Android) from CAF using the linux kernel, lack of length validation check for value received from caller function used as an array index for WMA interfaces can lead to OOB write in WLAN HOST.
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Analysis
by VulDB Data Team • 05/17/2023
This vulnerability exists within the Linux kernel implementations used across various Android platforms including Android for MSM, Firefox OS for MSM, and QRD Android systems developed by Qualcomm Atheros. The flaw manifests as a critical buffer overflow condition in the WLAN HOST subsystem where insufficient validation occurs on input parameters passed from caller functions. The vulnerability specifically targets the WMA interfaces which handle wireless multimedia applications and are integral to the wireless communication stack. When malicious or malformed data is received from a caller function, the system fails to validate the length of this data before using it as an array index, creating a predictable path for out-of-bounds memory writes.
The technical execution of this vulnerability involves a classic buffer overflow scenario where the index validation is bypassed, allowing arbitrary memory locations to be overwritten. This occurs within the wireless multimedia application interface layer where the kernel processes incoming data packets or configuration parameters. The lack of proper bounds checking creates a condition where an attacker can manipulate the input value to point beyond the allocated memory boundaries of the target array. This flaw directly maps to CWE-129 which describes improper validation of array index bounds, and potentially CWE-787 which covers out-of-bounds write conditions. The vulnerability is particularly dangerous because it operates at the kernel level where successful exploitation can lead to complete system compromise.
The operational impact of CVE-2018-11903 extends beyond simple data corruption as it represents a critical security weakness that could enable privilege escalation attacks. When an attacker successfully exploits this vulnerability, they can manipulate memory contents in the WLAN HOST subsystem which may contain critical system data structures or even code execution pointers. The affected platforms include numerous Qualcomm-based devices running Android and Firefox OS, making this vulnerability widespread across mobile and embedded systems. Attackers could potentially leverage this condition to execute arbitrary code with kernel privileges, leading to complete device compromise, data exfiltration, or persistent backdoor installation. This vulnerability also aligns with ATT&CK technique T1068 which covers local privilege escalation and T1547 which covers persistence mechanisms through kernel-level modifications.
Mitigation strategies for this vulnerability should focus on implementing proper input validation and bounds checking within the kernel code handling WMA interfaces. System administrators should ensure all affected devices receive immediate security patches from their vendors, particularly those from Qualcomm and device manufacturers supporting these platforms. The patching process should include validation of all array indices before use, implementing proper length checks for parameters received from caller functions, and adding additional safeguards against malicious input data. Additionally, network monitoring should be enhanced to detect anomalous wireless communication patterns that might indicate exploitation attempts. Organizations should also consider implementing runtime protections such as kernel address space layout randomization and stack canaries to make exploitation more difficult. Regular security audits of kernel modules and wireless communication stacks should be conducted to identify similar validation flaws that could present analogous risks to system security and integrity.