CVE-2026-64366

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> HID: wacom: fix slab-out-of-bounds write in wacom_wac_queue_insert<br /> <br /> wacom_wac_queue_insert() calls kfifo_skip() in a loop when the kfifo<br /> doesn&amp;#39;t have enough space for the incoming report. If the kfifo is<br /> empty, kfifo_skip() reads stale data left in the kmalloc&amp;#39;d buffer<br /> via __kfifo_peek_n() and interprets it as a record length, advancing<br /> fifo-&gt;out by that garbage value. This corrupts the internal kfifo<br /> state, causing kfifo_unused() to return a value much larger than the<br /> actual buffer size, which bypasses __kfifo_in_r()&amp;#39;s guard:<br /> <br /> if (len + recsize &gt; kfifo_unused(fifo))<br /> return 0;<br /> <br /> kfifo_copy_in() then performs an out-of-bounds memcpy, writing up to<br /> 3842 bytes past the 256-byte buffer.<br /> <br /> Add a !kfifo_is_empty() condition to the while loop so kfifo_skip()<br /> is never called on an empty fifo, and check the return value of<br /> kfifo_in() to reject reports that are too large for the fifo.