{ "schema_version": "1.6.1", "id": "RPI-CVE-2026-64366", "modified": "2026-10-09T11:39:44Z", "upstream": [ "CVE-2026-64366" ], "published": "2026-07-25T08:51:45Z", "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->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.", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H" } ], "affected": [ { "package": { "ecosystem": "Raspberry Pi OS:13", "name": "linux" }, "versions": [ "1:6.18.29-1+rpt1", "1:6.18.33-1+rpt1", "1:6.18.34-1+rpt1" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.18.29+rpt-rpi-2712", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v6", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v7", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v8", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v8-rt", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-2712", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v6", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v7", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8-rt", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-2712", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v6", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v7", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8-rt", "binary_version": "1:6.18.34-1+rpt1" } ] }, "database_specific": { "per_version": { "1:6.18.29-1+rpt1": { "linux_commit": "66318c5b5cd8145a662303af12ed39ac07eb27cc", "upstream_version": "6.18.29", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.39" }, "1:6.18.33-1+rpt1": { "linux_commit": "95b85bebbedcaedfa7ca79116ed38b7376fba412", "upstream_version": "6.18.33", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.39" }, "1:6.18.34-1+rpt1": { "linux_commit": "c8c7494100e99ee05b11aaa4f0588a223a63d1af", "upstream_version": "6.18.34", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.39" } } } } ], "references": [ { "type": "ADVISORY", "url": "https://www.cve.org/CVERecord?id=CVE-2026-64366" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/ca899a926c11a59211b764b0155d9a1cdcc32b81" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/57bdd10ad50d68341f500a7b330f0d8949e510ec" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/6b3014ec0e9a390ca563030b2d7689921f0daef5" } ], "database_specific": { "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git", "upstream_modified": "2026-08-17T05:24:08Z", "severity": { "source": "kernel CNA", "cvss_v3_score": 8.8, "cvss_v3_severity": "High", "scenario": "AV:A - The Wacom driver accepts Bluetooth HID devices, whose attacker-controlled descriptors and reports reach wacom_raw_event through HIDP or UHID. A malicious peripheral within Bluetooth range can therefore trigger the flaw.\nAC:L - A single oversized crafted report can deterministically corrupt the empty FIFO state and trigger the overwrite. No race or condition outside the attacker's control is required.\nPR:N - A connected malicious Bluetooth peripheral needs no account or kernel capability on the target. The report-processing path contains no privilege or authentication check.\nUI:N - Once the malicious peripheral is connected, it can transmit the triggering report without any concurrent victim action.\nS:U - The corruption occurs inside the host kernel and compromises resources governed by that same security authority; it does not inherently cross a VM or IOMMU boundary.\nC:H - The large attacker-controlled heap overwrite can corrupt adjacent kernel objects and be developed into code-execution or arbitrary-memory-access primitives, exposing kernel and process memory.\nI:H - The report supplies thousands of attacker-controlled bytes beyond a small slab object, enabling corruption of adjacent objects and potential kernel control-flow hijacking.\nA:H - The extensive slab overwrite can immediately cause a kernel oops or panic, and the triggering report can be sent repeatedly." } } }