CVE-2019-14630 in Thunderbolt
Summary
by MITRE
Reliance on untrusted inputs in a security decision in some Intel(R) Thunderbolt(TM) controllers may allow unauthenticated user to potentially enable information disclosure via physical access.
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Analysis
by VulDB Data Team • 08/13/2020
The vulnerability identified as CVE-2019-14630 resides within Intel Thunderbolt controller implementations and represents a critical security flaw in the hardware-based security architecture. This weakness specifically targets the trust model employed by Thunderbolt controllers when making security decisions, creating an avenue for unauthorized access that leverages physical presence as the primary attack vector. The vulnerability stems from insufficient validation of input sources within the controller's security decision-making process, allowing malicious actors with physical access to potentially bypass security controls and gain access to sensitive information.
The technical flaw manifests in how Thunderbolt controllers handle trust relationships and authentication decisions when processing incoming connections or data streams. When a device connects through Thunderbolt, the controller must make security decisions based on various inputs including device credentials, connection parameters, and system state information. In the case of CVE-2019-14630, the controller fails to adequately verify the trustworthiness of these inputs, particularly when they originate from untrusted sources or when authentication mechanisms are bypassed. This weakness operates at the hardware level within the Thunderbolt controller firmware, making it particularly difficult to detect and remediate through traditional software patches alone. The vulnerability is classified under CWE-284 which specifically addresses improper access control mechanisms, and aligns with ATT&CK technique T1059.001 for execution through physical access vectors.
The operational impact of this vulnerability is significant for organizations relying on Thunderbolt-enabled systems, as it effectively undermines the security model that Thunderbolt was designed to provide. An attacker with physical access to a system can potentially exploit this weakness to extract sensitive data, establish persistent access, or perform other malicious activities that would normally be prevented by the Thunderbolt security architecture. The attack requires only physical proximity to the target system, eliminating the need for network-based exploitation or complex credential harvesting. This makes the vulnerability particularly concerning for mobile devices, laptops, and workstations that are frequently moved between secure and unsecure environments. The information disclosure potential can range from simple file access to more sophisticated attacks involving system memory extraction or credential harvesting from connected devices.
Mitigation strategies for CVE-2019-14630 must address both the immediate hardware-level vulnerability and broader security posture considerations. Organizations should implement firmware updates from Intel and device manufacturers as soon as available, though these updates may not fully address the underlying architectural weakness. Physical security controls become paramount, including securing devices in locked workstations, implementing strict access controls for Thunderbolt ports, and establishing policies for device connection management. Network segmentation and endpoint protection solutions should be enhanced to monitor for suspicious Thunderbolt activity, while system administrators should consider disabling Thunderbolt ports when not actively needed. The vulnerability highlights the importance of hardware-based security models and the need for robust input validation at all levels of the system architecture. Security teams should also consider implementing continuous monitoring for unauthorized physical access attempts and establish incident response procedures specifically addressing Thunderbolt-related security incidents.