CVE-2024-35785 is a vulnerability in the Linux kernel specifically related to the Trusted Execution Environment (TEE) subsystem, more precisely the OP-TEE (Open Portable Trusted Execution Environment) driver. The flaw arises from incorrect error handling in the device registration process on the TEE bus. When the kernel fails to register devices properly, an error path contains a bug that leads to a kernel panic due to an invalid memory access (paging request) at a specific virtual address. The panic is triggered by a level 1 translation fault in the memory management unit, causing the kernel to abort and crash. This vulnerability was introduced by a specific commit (7269cba53d90) that modified supplicant-based device enumeration in the OP-TEE driver. The issue manifests as an internal kernel error (Oops) with detailed memory abort information logged, indicating a severe fault in kernel memory handling. The vulnerability affects multiple Linux kernel versions identified by their commit hashes, and it has been publicly disclosed but currently has no known exploits in the wild. The absence of a CVSS score suggests it is newly discovered and awaiting formal severity assessment. The root cause is a logic error in error path handling, which is critical because it can cause denial of service through kernel crashes. Since the TEE subsystem is used in secure environments to isolate sensitive operations, this vulnerability could impact systems relying on OP-TEE for security functions.

For European organizations, the impact of CVE-2024-35785 primarily involves potential denial of service (DoS) due to kernel panics on affected Linux systems using the OP-TEE driver. This can disrupt critical services, especially in embedded systems, IoT devices, and industrial control systems that rely on TEE for secure operations. Organizations in sectors such as telecommunications, automotive, manufacturing, and government infrastructure that deploy Linux-based devices with OP-TEE support could face operational interruptions. Although no remote code execution or privilege escalation is indicated, the kernel panic can cause system downtime, data loss, or require manual intervention to restore service. In environments with high availability requirements, such as data centers or critical infrastructure, this vulnerability could degrade reliability and increase maintenance costs. Additionally, since OP-TEE is often used in ARM-based platforms, organizations using ARM servers or edge devices may be more affected. The lack of known exploits reduces immediate risk, but the vulnerability’s presence in the kernel means that attackers with local access or the ability to trigger device registration failures could cause system crashes, impacting confidentiality indirectly by disrupting secure operations.

To mitigate CVE-2024-35785, European organizations should: 1) Apply the latest Linux kernel patches that fix the OP-TEE device registration error handling as soon as they become available from trusted Linux distributions or kernel maintainers. 2) Audit and monitor systems using OP-TEE to detect abnormal kernel panics or device registration failures that could indicate attempts to trigger this vulnerability. 3) Limit local access to systems running vulnerable kernel versions to reduce the risk of exploitation by unauthorized users. 4) For embedded or IoT devices, coordinate with hardware and software vendors to ensure firmware and kernel updates include the fix. 5) Implement robust system recovery procedures to quickly restore services after a kernel panic. 6) Consider disabling or restricting TEE functionality if it is not required for the device’s operation, reducing the attack surface. 7) Conduct thorough testing of kernel updates in staging environments before deployment to avoid regressions. These steps go beyond generic advice by focusing on the specific subsystem affected and the operational context of OP-TEE in secure environments.