{"id":"CVE-2026-64365","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: letsketch: fix UAF on inrange_timer at driver unbind\n\nletsketch_driver does not provide a .remove callback, but\nletsketch_probe() arms a per-device timer:\n\n    tim…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: letsketch: fix UAF on inrange_timer at driver unbind\n\nletsketch_driver does not provide a .remove callback, but\nletsketch_probe() arms a per-device timer:\n\n    tim…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-416"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.17, < 6.1.178","linux_kernel >= 6.2, < 6.6.145","linux_kernel >= 6.7, < 6.12.96","linux_kernel >= 6.13, < 6.18.39","linux_kernel >= 6.19, < 7.1.4","linux_kernel = 7.2"],"patched":["linux_kernel 7.1.4"],"published":"2026-07-25","updated":"2026-09-04","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64365","references":[{"url":"https://git.kernel.org/stable/c/17f5928d7010bc9e002930326b59e60e40c09ee3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2bb6e7143cf70ed281822d26c1848b2897ac36e9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3eca1a8165b5e7996e699e9df76cb4645e184d42","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/46c8beeccd8ab2c863827254a85ea877654a3534","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/523db788c0f84612707638e266e8957ca7e3a756","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/df3d8aa1a9392da3de66398e7a03422463806b21","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00129,"epssPercentile":0.021,"ingestedAt":"2026-09-05T13:39:57.039Z","slug":"CVE-2026-64365","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nHID: letsketch: fix UAF on inrange_timer at driver unbind\n\nletsketch_driver does not provide a .remove callback, but\nletsketch_probe() arms a per-device timer:\n\n    timer_setup(&data->inrange_timer, letsketch_inrange_timeout, 0);\n\nThe timer is re-armed from letsketch_raw_event() with a 100 ms\ntimeout on every pen-in-range report, and its callback dereferences\ndata->input_tablet to deliver a synthetic BTN_TOOL_PEN release.\n\nletsketch_data is allocated with devm_kzalloc(), and its input_dev\nfields are devm-allocated via letsketch_setup_input_tablet().  On\ndevice unbind (USB unplug or rmmod), the HID core runs its default\nteardown and devm cleanup frees both letsketch_data and the input\ndevices.  Because no .remove callback exists, nothing drains the\ntimer first: if raw_event armed it within ~100 ms of the unbind,\nthe pending timer fires on freed memory.  This is a UAF read of\ndata and of data->input_tablet, followed by input_report_key() /\ninput_sync() into the freed input_dev.\n\nThe same problem can occur on the probe error path: if\nhid_hw_start() enabled I/O on an always-poll-quirk device and then\nfailed, raw_event may have armed the timer before devm releases\ndata.\n\nFix by adding a .remove callback that calls hid_hw_stop() first.\nhid_hw_stop() synchronously kills the URBs that deliver raw_event(),\nso once it returns no path can re-arm the timer.  timer_shutdown_sync()\nthen drains any in-flight callback and permanently disables further\nmod_timer() calls.  Apply the same timer_shutdown_sync() in the probe\nerror path so the timer is guaranteed not to outlive data.\n\n## Affected\n\n- `linux_kernel >= 5.17, < 6.1.178`\n- `linux_kernel >= 6.2, < 6.6.145`\n- `linux_kernel >= 6.7, < 6.12.96`\n- `linux_kernel >= 6.13, < 6.18.39`\n- `linux_kernel >= 6.19, < 7.1.4`\n- `linux_kernel = 7.2`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.1.4`","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}