CVE-2024-46853 is a high-severity out-of-bounds memory access vulnerability in the Linux kernel's nxp-fspi SPI driver. It occurs when writing data that is not 4-byte aligned to the TX FIFO, causing a KASAN (Kernel Address Sanitizer) slab-out-of-bounds error. The issue is triggered by writing 3 bytes of data to a NOR chip, leading to a read beyond the allocated memory region. This flaw has been fixed by correcting the memcpy length to prevent out-of-bounds access.