CVE-2024-39466 in Linux
Summary
by MITRE • 06/25/2024
In the Linux kernel, the following vulnerability has been resolved:
thermal/drivers/qcom/lmh: Check for SCM availability at probe
Up until now, the necessary scm availability check has not been performed, leading to possible null pointer dereferences (which did happen for me on RB1).
Fix that.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 04/07/2026
The vulnerability identified as CVE-2024-39466 resides within the Linux kernel's thermal management subsystem, specifically in the Qualcomm LMH (Level Management Hardware) driver component. This flaw represents a critical null pointer dereference issue that can occur during the device probe phase of kernel initialization. The vulnerability manifests when the system attempts to access SCM (Secure Channel Manager) resources without first verifying their availability, creating a scenario where the kernel may attempt to dereference a null pointer reference. The issue was particularly evident on RB1 platforms where the problematic behavior was observed firsthand, highlighting the real-world impact of this oversight in the kernel's hardware abstraction layer.
The technical root cause of this vulnerability stems from inadequate initialization sequence validation within the Qualcomm LMH driver's probe function. The driver fails to perform a proper SCM availability check before proceeding with operations that depend on SCM services. This oversight creates a race condition and potential crash scenario where the kernel's thermal management subsystem attempts to utilize SCM resources that have not yet been properly initialized or are unavailable. The absence of this validation step means that when the driver's probe routine executes, it may proceed with operations expecting SCM services to be available, resulting in a null pointer dereference that terminates the kernel execution and potentially causes system instability.
From an operational perspective, this vulnerability poses significant risks to embedded systems and mobile devices running Linux kernels that incorporate the Qualcomm LMH thermal driver. The impact extends beyond simple system crashes to potentially compromise the thermal management capabilities of affected devices, which could lead to overheating issues or complete system failure. The vulnerability affects systems where the Qualcomm LMH driver is loaded and initialized, particularly those in automotive, mobile, or embedded computing environments where thermal management is critical for system reliability and safety. The null pointer dereference can cause immediate system termination, making this a high-severity issue that requires prompt remediation across affected kernel versions.
The mitigation strategy for CVE-2024-39466 involves implementing proper SCM availability checks within the driver's probe function before any SCM-dependent operations are attempted. This aligns with the principles outlined in CWE-476, which addresses null pointer dereference vulnerabilities, and follows the ATT&CK framework's system binary exploitation techniques. The fix requires modification of the driver's initialization sequence to include verification that SCM services are properly available and accessible before proceeding with resource allocation and operation setup. This approach ensures that the thermal management subsystem maintains system stability and prevents the kernel from attempting to access unavailable hardware resources, thereby maintaining the integrity of the system's thermal control mechanisms. The solution should be implemented as a kernel patch that modifies the probe routine to perform SCM availability validation, preventing the null pointer dereference condition that leads to system instability.