CVE-2015-4422 in Mate 7
Summary
by MITRE
The TEEOS module in Huawei Mate 7 (Mate7-TL10) smartphone before V100R001CHNC00B126SP03 allows local users with root permissions to gain privileges or cause a denial of service (memory corruption) via a crafted application.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 11/26/2019
The vulnerability identified as CVE-2015-4422 affects the Trust Execution Environment Operating System module within Huawei Mate 7 smartphones running firmware versions prior to V100R001CHNC00B126SP03. This represents a critical security flaw in the TEEOS component that governs the secure execution environment of the device. The vulnerability specifically targets the secure world execution context where sensitive operations and cryptographic functions are processed, making it particularly dangerous for mobile security infrastructure. The affected device model Mate7-TL10 operates with a TEEOS implementation that fails to properly validate input parameters from untrusted applications, creating an exploitable condition within the secure execution environment.
The technical flaw manifests as a memory corruption vulnerability that occurs when a crafted application attempts to interact with the TEEOS module through improper parameter handling or buffer manipulation. This memory corruption vulnerability allows for privilege escalation from a local user with root access to potentially gain elevated privileges within the secure execution environment. The vulnerability stems from inadequate input validation mechanisms within the TEEOS module, which fails to properly sanitize or verify the legitimacy of data structures passed from the rich execution environment to the secure world. This weakness creates a pathway for malicious code to manipulate the secure environment's memory layout, potentially leading to complete system compromise or denial of service conditions.
From an operational perspective, this vulnerability poses significant risks to mobile device security as it allows a local attacker with root access to escalate privileges within the Trust Execution Environment. The TEEOS module typically handles sensitive operations including cryptographic key storage, secure authentication processes, and protected data processing, making this vulnerability particularly dangerous. A successful exploitation could enable attackers to access secure storage areas, extract cryptographic keys, or manipulate secure applications that depend on the TEEOS for protection. The denial of service aspect of this vulnerability means that even if privilege escalation is not achieved, the memory corruption could cause the secure execution environment to crash or become unresponsive, effectively disabling critical security functions.
The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which covers heap-based buffer overflow scenarios, as the memory corruption occurs through improper handling of data structures within the secure execution environment. From an ATT&CK framework perspective, this vulnerability maps to T1068, which involves the abuse of remote services, and T1059, covering command and scripting interpreter usage, as exploitation would require executing malicious code within the secure environment. Organizations and users should immediately update their Huawei Mate 7 devices to firmware version V100R001CHNC00B126SP03 or later to mitigate this vulnerability. The update process should include verification of the firmware integrity and proper installation of security patches that address the input validation flaws in the TEEOS module. Additionally, security teams should implement monitoring for unauthorized root access attempts and suspicious application behavior that might indicate exploitation attempts. The vulnerability underscores the importance of secure coding practices in TEE environments and the necessity of thorough security testing for all components that handle sensitive data processing within mobile platforms.