CVE-2017-18292 in Snapdragon Automobile
Summary
by MITRE
Secure app running in non secure space can restart TZ by calling Widevine app API repeatedly in Snapdragon Automobile, Snapdragon Mobile and Snapdragon Wear in versions MSM8909W, MSM8996AU, SD 210/SD 212/SD 205, SD 410/12, SD 425, SD 430, SD 450, SD 615/16/SD 415, SD 617, SD 625, SD 650/52, SD 800, SD 810, SD 820, SD 820A.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 05/30/2023
The vulnerability identified as CVE-2017-18292 represents a critical security flaw in Qualcomm's Snapdragon automotive and mobile platform implementations that affects the Trusted Execution Environment (TEE) architecture. This issue specifically targets devices running in non-secure execution modes that can potentially manipulate the Trusted OS through repeated API calls to the Widevine application, which is designed to handle digital rights management for protected content. The vulnerability exists within the Snapdragon Automotive platforms including MSM8909W, MSM8996AU, and various Snapdragon mobile and wear platforms such as SD 210/SD 212/SD 205, SD 410/12, SD 425, SD 430, SD 450, SD 615/16/SD 415, SD 617, SD 625, SD 650/52, SD 800, SD 810, SD 820, and SD 820A chipsets.
The technical root cause of this vulnerability stems from insufficient input validation and access control mechanisms within the Widevine application programming interface. When a secure application operating in a non-secure execution context repeatedly invokes the Widevine API, it can trigger a sequence of operations that ultimately leads to the restart of the Trusted Zone (TZ) component. This behavior violates the fundamental security principle that the TEE should remain isolated and protected from unauthorized access attempts. The flaw essentially allows an attacker to perform a denial-of-service attack against the TEE by repeatedly invoking the API, causing the system to reset the trusted execution environment and potentially exposing sensitive operations to unauthorized manipulation. This vulnerability aligns with CWE-362, which describes a race condition in a security-critical section of code, and represents a significant deviation from the expected security boundaries of the TEE architecture.
The operational impact of this vulnerability is substantial as it compromises the integrity and availability of the Trusted Execution Environment across affected automotive and mobile platforms. An attacker with access to a non-secure application context could potentially disrupt the normal operation of the TEE, which is responsible for handling sensitive cryptographic operations, secure boot processes, and protected media decoding. The ability to repeatedly restart the TZ component could be exploited to bypass security measures, disrupt secure services, or create conditions that might allow for more sophisticated attacks. In automotive applications, this vulnerability could potentially affect vehicle infotainment systems, telematics modules, and other security-critical components that rely on secure execution environments. The vulnerability also aligns with ATT&CK technique T1068, which describes the use of local privilege escalation to gain access to restricted capabilities, and T1499, which covers the disruption of services through resource exhaustion.
Mitigation strategies for CVE-2017-18292 should focus on implementing robust API access controls and rate limiting mechanisms within the Widevine application interface. System administrators and device manufacturers should ensure that firmware updates are applied promptly to address this vulnerability, as Qualcomm has released patches for affected platforms. The implementation of enhanced input validation and authentication checks for API calls can help prevent unauthorized access attempts to the Trusted Zone. Additionally, monitoring systems should be deployed to detect unusual patterns of API invocation that might indicate exploitation attempts. Device manufacturers should also consider implementing more stringent access controls for non-secure applications attempting to interact with secure components, and regular security assessments should be conducted to verify the effectiveness of these mitigations. The vulnerability highlights the importance of maintaining strict separation between secure and non-secure execution contexts, and the need for comprehensive testing of all interfaces that provide access to trusted execution environments.