{"id":"CVE-2026-64366","summary":"HID: wacom: fix slab-out-of-bounds write in wacom_wac_queue_insert","details":"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 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-\u003eout 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 \u003e 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.","modified":"2026-07-28T04:03:04.312818050Z","published":"2026-07-25T08:50:20.612Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64366.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/57bdd10ad50d68341f500a7b330f0d8949e510ec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6b3014ec0e9a390ca563030b2d7689921f0daef5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ca899a926c11a59211b764b0155d9a1cdcc32b81"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64366.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64366"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5e013ad206895e72d7da41bc1ae89d8cb499c3aa"},{"fixed":"ca899a926c11a59211b764b0155d9a1cdcc32b81"},{"fixed":"57bdd10ad50d68341f500a7b330f0d8949e510ec"},{"fixed":"6b3014ec0e9a390ca563030b2d7689921f0daef5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64366.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.15.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64366.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}