CVE-2023-54027 in Linux
Summary
by MITRE • 12/24/2025
In the Linux kernel, the following vulnerability has been resolved:
iio: core: Prevent invalid memory access when there is no parent
Commit 813665564b3d ("iio: core: Convert to use firmware node handle instead of OF node") switched the kind of nodes to use for label retrieval in device registration. Probably an unwanted change in that commit was that if the device has no parent then NULL pointer is accessed. This is what happens in the stock IIO dummy driver when a new entry is created in configfs:
# mkdir /sys/kernel/config/iio/devices/dummy/foo BUG: kernel NULL pointer dereference, address: ... ... Call Trace: __iio_device_register iio_dummy_probe
Since there seems to be no reason to make a parent device of an IIO dummy device mandatory, let’s prevent the invalid memory access in __iio_device_register when the parent device is NULL. With this change, the IIO dummy driver works fine with configfs.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 12/26/2025
The vulnerability CVE-2023-54027 represents a critical null pointer dereference issue within the Linux kernel's Industrial I/O (IIO) subsystem core functionality. This flaw manifests specifically during device registration processes when the IIO framework attempts to access memory locations without proper validation of parent device existence. The vulnerability stems from a code modification introduced in commit 813665564b3d which altered how device nodes are handled for label retrieval during registration. This change inadvertently created a scenario where the system fails to properly check for null parent device pointers, leading to immediate kernel panic conditions when processing IIO dummy devices through configfs interfaces.
The technical implementation of this vulnerability occurs within the __iio_device_register function where the kernel attempts to dereference a NULL pointer when no parent device is present. This memory access violation happens exclusively in the context of IIO dummy driver operations when creating new entries in the configfs filesystem through commands like mkdir /sys/kernel/config/iio/devices/dummy/foo. The underlying flaw demonstrates poor defensive programming practices where the code assumes parent device existence without proper null validation checks. According to CWE classification, this represents a CWE-476 Null Pointer Dereference vulnerability, which falls under the broader category of improper null pointer handling in kernel space operations.
The operational impact of CVE-2023-54027 extends beyond simple system crashes to potentially disrupt critical embedded systems and industrial automation environments that rely on IIO subsystem functionality. When exploited through the configfs interface, this vulnerability can cause complete system hangs or reboot cycles, affecting device drivers that depend on proper IIO device registration sequences. The vulnerability affects systems using the IIO dummy driver specifically when attempting to create device entries through the kernel's configuration filesystem, which is commonly used in development and testing scenarios. From an ATT&CK framework perspective, this vulnerability could be leveraged by adversaries to achieve denial of service conditions or potentially escalate privileges through kernel exploitation techniques.
Mitigation strategies for CVE-2023-54027 involve implementing proper null pointer validation within the IIO core registration functions before attempting memory access operations. The fix should ensure that when a parent device is NULL, the code path properly handles this condition without attempting to dereference null pointers. System administrators should update to kernel versions containing the patched commit that addresses this specific null pointer dereference issue. Organizations relying on IIO dummy drivers in production environments should conduct thorough testing of their configfs operations to ensure the vulnerability has been properly resolved. Additionally, monitoring systems should be configured to detect kernel panic conditions that may indicate this vulnerability being exploited in the wild, as the immediate system crashes provide clear indicators of successful exploitation attempts.