CVE-2024-42076 is a medium severity vulnerability in the Linux kernel's CAN J1939 networking subsystem. The issue arises because the function j1939_send_one() creates a full frame including unused data but does not initialize this unused data, leading to a kernel information leak. This uninitialized data can be exposed via the raw_recvmsg() system call, potentially leaking kernel memory contents. The vulnerability has been identified and fixed by initializing the unused data in the affected function.