GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

FKIE_CVE-2026-64365

Vulnerability from fkie_nvd - Published: 2026-07-25 10:17 - Updated: 2026-09-04 20:40
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: HID: letsketch: fix UAF on inrange_timer at driver unbind letsketch_driver does not provide a .remove callback, but letsketch_probe() arms a per-device timer: timer_setup(&data->inrange_timer, letsketch_inrange_timeout, 0); The timer is re-armed from letsketch_raw_event() with a 100 ms timeout on every pen-in-range report, and its callback dereferences data->input_tablet to deliver a synthetic BTN_TOOL_PEN release. letsketch_data is allocated with devm_kzalloc(), and its input_dev fields are devm-allocated via letsketch_setup_input_tablet(). On device unbind (USB unplug or rmmod), the HID core runs its default teardown and devm cleanup frees both letsketch_data and the input devices. Because no .remove callback exists, nothing drains the timer first: if raw_event armed it within ~100 ms of the unbind, the pending timer fires on freed memory. This is a UAF read of data and of data->input_tablet, followed by input_report_key() / input_sync() into the freed input_dev. The same problem can occur on the probe error path: if hid_hw_start() enabled I/O on an always-poll-quirk device and then failed, raw_event may have armed the timer before devm releases data. Fix by adding a .remove callback that calls hid_hw_stop() first. hid_hw_stop() synchronously kills the URBs that deliver raw_event(), so once it returns no path can re-arm the timer. timer_shutdown_sync() then drains any in-flight callback and permanently disables further mod_timer() calls. Apply the same timer_shutdown_sync() in the probe error path so the timer is guaranteed not to outlive data.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/17f5928d7010bc9e002930326b59e60e40c09ee3Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/2bb6e7143cf70ed281822d26c1848b2897ac36e9Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3eca1a8165b5e7996e699e9df76cb4645e184d42Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/46c8beeccd8ab2c863827254a85ea877654a3534Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/523db788c0f84612707638e266e8957ca7e3a756Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/df3d8aa1a9392da3de66398e7a03422463806b21Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 7.2
linux linux_kernel 7.2
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/hid/hid-letsketch.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2bb6e7143cf70ed281822d26c1848b2897ac36e9",
              "status": "affected",
              "version": "33a5c2793451770cb6dcf0cc35c76cfd4b045513",
              "versionType": "git"
            },
            {
              "lessThan": "523db788c0f84612707638e266e8957ca7e3a756",
              "status": "affected",
              "version": "33a5c2793451770cb6dcf0cc35c76cfd4b045513",
              "versionType": "git"
            },
            {
              "lessThan": "17f5928d7010bc9e002930326b59e60e40c09ee3",
              "status": "affected",
              "version": "33a5c2793451770cb6dcf0cc35c76cfd4b045513",
              "versionType": "git"
            },
            {
              "lessThan": "3eca1a8165b5e7996e699e9df76cb4645e184d42",
              "status": "affected",
              "version": "33a5c2793451770cb6dcf0cc35c76cfd4b045513",
              "versionType": "git"
            },
            {
              "lessThan": "df3d8aa1a9392da3de66398e7a03422463806b21",
              "status": "affected",
              "version": "33a5c2793451770cb6dcf0cc35c76cfd4b045513",
              "versionType": "git"
            },
            {
              "lessThan": "46c8beeccd8ab2c863827254a85ea877654a3534",
              "status": "affected",
              "version": "33a5c2793451770cb6dcf0cc35c76cfd4b045513",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/hid/hid-letsketch.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.17"
            },
            {
              "lessThan": "5.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.96",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.39",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "BCE8EB1C-BA21-4585-B9DD-EBD770D8C66E",
              "versionEndExcluding": "6.1.178",
              "versionStartIncluding": "5.17",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7046B092-F810-4440-ACE6-60218518EECE",
              "versionEndExcluding": "6.6.145",
              "versionStartIncluding": "6.2",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2",
              "versionEndExcluding": "6.12.96",
              "versionStartIncluding": "6.7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7",
              "versionEndExcluding": "6.18.39",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42",
              "versionEndExcluding": "7.1.4",
              "versionStartIncluding": "6.19",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "5E8B9085-7ADB-4A05-89EF-12949B6A0509",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "1FC0D50D-9D58-4947-A197-A5A3FF07E7E3",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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    timer_setup(\u0026data-\u003einrange_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-\u003einput_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-\u003einput_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."
    }
  ],
  "id": "CVE-2026-64365",
  "lastModified": "2026-09-04T20:40:58.803",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-07-25T10:17:19.280",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/17f5928d7010bc9e002930326b59e60e40c09ee3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/2bb6e7143cf70ed281822d26c1848b2897ac36e9"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3eca1a8165b5e7996e699e9df76cb4645e184d42"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/46c8beeccd8ab2c863827254a85ea877654a3534"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/523db788c0f84612707638e266e8957ca7e3a756"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/df3d8aa1a9392da3de66398e7a03422463806b21"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.