CVE-2018-3578 in Android
Summary
by MITRE
Type mismatch for ie_len can cause the WLAN driver to allocate less memory on the heap due to implicit casting leading to a heap buffer overflow in all Android releases from CAF (Android for MSM, Firefox OS for MSM, QRD Android) using the Linux Kernel.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 02/15/2020
The vulnerability described in CVE-2018-3578 represents a critical heap buffer overflow condition affecting Android devices that utilize Qualcomm's Android for MSM, Firefox OS for MSM, and QRD Android platforms. This issue stems from an implicit type casting error within the WLAN driver component that processes IEEE 802.11 management frames. The flaw manifests when the driver handles the ie_len field in beacon frames, where the length parameter undergoes unintended type conversion that results in insufficient heap memory allocation. This type mismatch creates a scenario where the system allocates memory based on a smaller data type value, leaving the actual buffer vulnerable to overflow conditions when processing legitimate but potentially malformed wireless frames.
The technical root cause of this vulnerability lies in the improper handling of unsigned integer types during the processing of wireless management frames. When the WLAN driver receives a beacon frame containing an ie_len field, the implicit casting from a larger unsigned integer type to a smaller one causes the driver to allocate memory based on an incorrect length value. This memory allocation shortfall directly enables attackers to craft specially formatted beacon frames that, when processed by the vulnerable driver, trigger heap corruption. The flaw specifically impacts the Linux kernel implementations used in these mobile platforms, making it particularly concerning given the widespread adoption of Qualcomm's MSM chipsets in Android devices.
The operational impact of this vulnerability extends beyond simple memory corruption, creating potential pathways for privilege escalation and system compromise. An attacker positioned within wireless range of a vulnerable device could exploit this condition by transmitting maliciously crafted beacon frames that cause the WLAN driver to overflow heap buffers. This overflow can result in arbitrary code execution within the kernel context, potentially allowing attackers to gain elevated privileges and execute malicious payloads on the target device. The vulnerability affects all Android releases utilizing the affected kernel components, making it particularly dangerous as it impacts a broad range of mobile devices that depend on Qualcomm's wireless infrastructure.
Mitigation strategies for CVE-2018-3578 require both immediate patching and operational security measures. Device manufacturers must implement kernel patches that correct the type casting behavior in the WLAN driver component, ensuring proper handling of the ie_len field through explicit type conversion rather than relying on implicit casting. Security researchers should monitor for exploitation attempts and implement network-based detection mechanisms that can identify malformed beacon frames targeting this specific vulnerability. Organizations should also consider implementing wireless network segmentation and monitoring to detect suspicious wireless activity that might indicate exploitation attempts. The vulnerability aligns with CWE-129, which describes improper validation of array indices, and maps to ATT&CK techniques involving privilege escalation and code execution through kernel vulnerabilities. Given the nature of the flaw, regular security updates and proper kernel version management become critical defensive measures for maintaining device security.