CVE-2025-38394: 
Linux Ubuntu vulnerability analysis and mitigation

A memory corruption vulnerability was discovered in the Linux kernel's HID appletb-kbd driver. The vulnerability (CVE-2025-38394) was reported on July 25, 2025, affecting the input handler registration process in the appletbkbdprobe function (Kernel CVE).

The vulnerability occurs in the appletbkbdprobe function where an input handler is initialized and registered with the input core through inputregisterhandler(). When the input handler is registered, it is added to the global inputhandlerlist. If a probe failure occurs after inputregisterhandler(), the inputhandler memory is freed but remains in the inputhandlerlist, resulting in a use-after-free condition that corrupts the inputhandler_list (Kernel CVE).

When exploited, this vulnerability can lead to memory corruption of the inputhandlerlist, which is critical for input core functionality. The issue becomes apparent when new input devices are connected, as the system attempts to traverse the corrupted inputhandlerlist, potentially leading to system crashes or panics (Kernel CVE).

The fix involves ensuring the input handler is properly unregistered from input core through inputunregisterhandler() before memory deallocation (Kernel CVE).