{"id":"CVE-2026-64366","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: wacom: fix slab-out-of-bounds write in wacom_wac_queue_insert\n\nwacom_wac_queue_insert() calls kfifo_skip() in a loop when the kfifo\ndoesn't have enough space for t…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: wacom: fix slab-out-of-bounds write in wacom_wac_queue_insert\n\nwacom_wac_queue_insert() calls kfifo_skip() in a loop when the kfifo\ndoesn't have enough space for t…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","published":"2026-07-25","updated":"2026-07-27","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64366","references":[{"url":"https://git.kernel.org/stable/c/57bdd10ad50d68341f500a7b330f0d8949e510ec","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6b3014ec0e9a390ca563030b2d7689921f0daef5","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ca899a926c11a59211b764b0155d9a1cdcc32b81","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00253,"epssPercentile":0.17128,"ingestedAt":"2026-07-27T06:16:50.759Z","slug":"CVE-2026-64366","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nHID: wacom: fix slab-out-of-bounds write in wacom_wac_queue_insert\n\nwacom_wac_queue_insert() calls kfifo_skip() in a loop when the kfifo\ndoesn't have enough space for the incoming report. If the kfifo is\nempty, kfifo_skip() reads stale data left in the kmalloc'd buffer\nvia __kfifo_peek_n() and interprets it as a record length, advancing\nfifo->out by that garbage value. This corrupts the internal kfifo\nstate, causing kfifo_unused() to return a value much larger than the\nactual buffer size, which bypasses __kfifo_in_r()'s guard:\n\n  if (len + recsize > kfifo_unused(fifo))\n      return 0;\n\nkfifo_copy_in() then performs an out-of-bounds memcpy, writing up to\n3842 bytes past the 256-byte buffer.\n\nAdd a !kfifo_is_empty() condition to the while loop so kfifo_skip()\nis never called on an empty fifo, and check the return value of\nkfifo_in() to reject reports that are too large for the fifo.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}