Vulnerability-Lookup

GHSA-GMVX-6PFP-7MCV

Vulnerability from github – Published: 2026-05-28 12:30 – Updated: 2026-05-28 12:30

Details

In the Linux kernel, the following vulnerability has been resolved:

HID: appletb-kbd: fix UAF in inactivity-timer cleanup path

Commit 38224c472a03 ("HID: appletb-kbd: fix slab use-after-free bug in appletb_kbd_probe") added timer_delete_sync(&kbd->inactivity_timer) to both the probe close_hw error path and appletb_kbd_remove(), but the way it was wired in left the inactivity timer reachable during driver tear-down via two distinct windows.

Window A -- put_device() before timer_delete_sync():

put_device(&kbd->backlight_dev->dev);
timer_delete_sync(&kbd->inactivity_timer);

The inactivity_timer softirq reads kbd->backlight_dev and calls backlight_device_set_brightness() -> mutex_lock(&ops_lock). If a concurrent hid_appletb_bl unbind drops the last devm reference between these two calls, the backlight_device is freed and the mutex_lock() touches freed memory.

Window B -- backlight cleanup before hid_hw_stop():

if (kbd->backlight_dev) {
    timer_delete_sync(...);
    put_device(...);
}
hid_hw_close(hdev);
hid_hw_stop(hdev);

Even after Window A is closed, hid_hw_close()/hid_hw_stop() still run afterwards, so a late ".event" callback from the HID core (USB URB completion on real Apple hardware) can arrive after timer_delete_sync() drained the softirq but before put_device() drops the reference. That callback reaches reset_inactivity_timer(), which calls mod_timer() and re-arms the timer. The freshly re-armed timer can then fire on the about-to-be-freed backlight_device.

Both windows produce the same KASAN slab-use-after-free:

BUG: KASAN: slab-use-after-free in __mutex_lock+0x1aab/0x21c0 Read of size 8 at addr ffff88803ee9a108 by task swapper/0/0 Call Trace: __mutex_lock backlight_device_set_brightness appletb_inactivity_timer call_timer_fn run_timer_softirq handle_softirqs Allocated by task N: devm_backlight_device_register appletb_bl_probe Freed by task M: (concurrent hid_appletb_bl unbind path)

Close both windows at once by reworking the tear-down in appletb_kbd_remove() and in the probe close_hw error path so that

1) hid_hw_close()/hid_hw_stop() run before the backlight cleanup, guaranteeing no further .event callback can fire and re-arm the timer, and 2) inside the "if (kbd->backlight_dev)" block, timer_delete_sync() runs before put_device(), so the softirq is drained before the final reference is dropped.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-46213"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-28T10:16:36Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nHID: appletb-kbd: fix UAF in inactivity-timer cleanup path\n\nCommit 38224c472a03 (\"HID: appletb-kbd: fix slab use-after-free bug in\nappletb_kbd_probe\") added timer_delete_sync(\u0026kbd-\u003einactivity_timer) to\nboth the probe close_hw error path and appletb_kbd_remove(), but the\nway it was wired in left the inactivity timer reachable during driver\ntear-down via two distinct windows.\n\nWindow A -- put_device() before timer_delete_sync():\n\n\tput_device(\u0026kbd-\u003ebacklight_dev-\u003edev);\n\ttimer_delete_sync(\u0026kbd-\u003einactivity_timer);\n\nThe inactivity_timer softirq reads kbd-\u003ebacklight_dev and calls\nbacklight_device_set_brightness() -\u003e mutex_lock(\u0026ops_lock).  If a\nconcurrent hid_appletb_bl unbind drops the last devm reference\nbetween these two calls, the backlight_device is freed and the\nmutex_lock() touches freed memory.\n\nWindow B -- backlight cleanup before hid_hw_stop():\n\n\tif (kbd-\u003ebacklight_dev) {\n\t\ttimer_delete_sync(...);\n\t\tput_device(...);\n\t}\n\thid_hw_close(hdev);\n\thid_hw_stop(hdev);\n\nEven after Window A is closed, hid_hw_close()/hid_hw_stop() still run\nafterwards, so a late \".event\" callback from the HID core (USB URB\ncompletion on real Apple hardware) can arrive after\ntimer_delete_sync() drained the softirq but before put_device() drops\nthe reference.  That callback reaches reset_inactivity_timer(), which\ncalls mod_timer() and re-arms the timer.  The freshly re-armed timer\ncan then fire on the about-to-be-freed backlight_device.\n\nBoth windows produce the same KASAN slab-use-after-free:\n\n  BUG: KASAN: slab-use-after-free in __mutex_lock+0x1aab/0x21c0\n  Read of size 8 at addr ffff88803ee9a108 by task swapper/0/0\n  Call Trace:\n   \u003cIRQ\u003e\n   __mutex_lock\n   backlight_device_set_brightness\n   appletb_inactivity_timer\n   call_timer_fn\n   run_timer_softirq\n   handle_softirqs\n  Allocated by task N:\n   devm_backlight_device_register\n   appletb_bl_probe\n  Freed by task M:\n   (concurrent hid_appletb_bl unbind path)\n\nClose both windows at once by reworking the tear-down in\nappletb_kbd_remove() and in the probe close_hw error path so that\n\n 1) hid_hw_close()/hid_hw_stop() run before the backlight cleanup,\n    guaranteeing no further .event callback can fire and re-arm the\n    timer, and\n 2) inside the \"if (kbd-\u003ebacklight_dev)\" block, timer_delete_sync()\n    runs before put_device(), so the softirq is drained before the\n    final reference is dropped.",
  "id": "GHSA-gmvx-6pfp-7mcv",
  "modified": "2026-05-28T12:30:33Z",
  "published": "2026-05-28T12:30:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46213"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4db2af929279c799b5653a39eb0795c72baffca4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/59a79938ca5541fe55d675304116b7ea684afef0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/93d989e47bc316c793a69c6a332e053c90e29f02"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-46213 (GCVE-0-2026-46213)

Vulnerability from cvelistv5 – Published: 2026-05-28 09:40 – Updated: 2026-05-28 09:40

Title

HID: appletb-kbd: fix UAF in inactivity-timer cleanup path

Summary

In the Linux kernel, the following vulnerability has been resolved: HID: appletb-kbd: fix UAF in inactivity-timer cleanup path Commit 38224c472a03 ("HID: appletb-kbd: fix slab use-after-free bug in appletb_kbd_probe") added timer_delete_sync(&kbd->inactivity_timer) to both the probe close_hw error path and appletb_kbd_remove(), but the way it was wired in left the inactivity timer reachable during driver tear-down via two distinct windows. Window A -- put_device() before timer_delete_sync(): put_device(&kbd->backlight_dev->dev); timer_delete_sync(&kbd->inactivity_timer); The inactivity_timer softirq reads kbd->backlight_dev and calls backlight_device_set_brightness() -> mutex_lock(&ops_lock). If a concurrent hid_appletb_bl unbind drops the last devm reference between these two calls, the backlight_device is freed and the mutex_lock() touches freed memory. Window B -- backlight cleanup before hid_hw_stop(): if (kbd->backlight_dev) { timer_delete_sync(...); put_device(...); } hid_hw_close(hdev); hid_hw_stop(hdev); Even after Window A is closed, hid_hw_close()/hid_hw_stop() still run afterwards, so a late ".event" callback from the HID core (USB URB completion on real Apple hardware) can arrive after timer_delete_sync() drained the softirq but before put_device() drops the reference. That callback reaches reset_inactivity_timer(), which calls mod_timer() and re-arms the timer. The freshly re-armed timer can then fire on the about-to-be-freed backlight_device. Both windows produce the same KASAN slab-use-after-free: BUG: KASAN: slab-use-after-free in __mutex_lock+0x1aab/0x21c0 Read of size 8 at addr ffff88803ee9a108 by task swapper/0/0 Call Trace: <IRQ> __mutex_lock backlight_device_set_brightness appletb_inactivity_timer call_timer_fn run_timer_softirq handle_softirqs Allocated by task N: devm_backlight_device_register appletb_bl_probe Freed by task M: (concurrent hid_appletb_bl unbind path) Close both windows at once by reworking the tear-down in appletb_kbd_remove() and in the probe close_hw error path so that 1) hid_hw_close()/hid_hw_stop() run before the backlight cleanup, guaranteeing no further .event callback can fire and re-arm the timer, and 2) inside the "if (kbd->backlight_dev)" block, timer_delete_sync() runs before put_device(), so the softirq is drained before the final reference is dropped.

Severity

No CVSS data available.

Assigner

Linux

References

3 references

URL	Tags
https://git.kernel.org/stable/c/59a79938ca5541fe5…
https://git.kernel.org/stable/c/93d989e47bc316c79…
https://git.kernel.org/stable/c/4db2af929279c799b…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 38224c472a038fa9ccd4085511dd9f3d6119dbf9 , < 59a79938ca5541fe55d675304116b7ea684afef0 (git) Affected: 38224c472a038fa9ccd4085511dd9f3d6119dbf9 , < 93d989e47bc316c793a69c6a332e053c90e29f02 (git) Affected: 38224c472a038fa9ccd4085511dd9f3d6119dbf9 , < 4db2af929279c799b5653a39eb0795c72baffca4 (git) Affected: 51720dee3a61ebace36c3dcdd0b4a488e0970f29 (git) Affected: 6.15.6 , < 6.16 (semver)
Linux	Linux	Affected: 6.16 Unaffected: 0 , < 6.16 (semver) Unaffected: 6.18.32 , ≤ 6.18.* (semver) Unaffected: 7.0.9 , ≤ 7.0.* (semver) Unaffected: 7.1-rc4 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/hid/hid-appletb-kbd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "59a79938ca5541fe55d675304116b7ea684afef0",
              "status": "affected",
              "version": "38224c472a038fa9ccd4085511dd9f3d6119dbf9",
              "versionType": "git"
            },
            {
              "lessThan": "93d989e47bc316c793a69c6a332e053c90e29f02",
              "status": "affected",
              "version": "38224c472a038fa9ccd4085511dd9f3d6119dbf9",
              "versionType": "git"
            },
            {
              "lessThan": "4db2af929279c799b5653a39eb0795c72baffca4",
              "status": "affected",
              "version": "38224c472a038fa9ccd4085511dd9f3d6119dbf9",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "51720dee3a61ebace36c3dcdd0b4a488e0970f29",
              "versionType": "git"
            },
            {
              "lessThan": "6.16",
              "status": "affected",
              "version": "6.15.6",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/hid/hid-appletb-kbd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.32",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1-rc4",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.32",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.9",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1-rc4",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.15.6",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nHID: appletb-kbd: fix UAF in inactivity-timer cleanup path\n\nCommit 38224c472a03 (\"HID: appletb-kbd: fix slab use-after-free bug in\nappletb_kbd_probe\") added timer_delete_sync(\u0026kbd-\u003einactivity_timer) to\nboth the probe close_hw error path and appletb_kbd_remove(), but the\nway it was wired in left the inactivity timer reachable during driver\ntear-down via two distinct windows.\n\nWindow A -- put_device() before timer_delete_sync():\n\n\tput_device(\u0026kbd-\u003ebacklight_dev-\u003edev);\n\ttimer_delete_sync(\u0026kbd-\u003einactivity_timer);\n\nThe inactivity_timer softirq reads kbd-\u003ebacklight_dev and calls\nbacklight_device_set_brightness() -\u003e mutex_lock(\u0026ops_lock).  If a\nconcurrent hid_appletb_bl unbind drops the last devm reference\nbetween these two calls, the backlight_device is freed and the\nmutex_lock() touches freed memory.\n\nWindow B -- backlight cleanup before hid_hw_stop():\n\n\tif (kbd-\u003ebacklight_dev) {\n\t\ttimer_delete_sync(...);\n\t\tput_device(...);\n\t}\n\thid_hw_close(hdev);\n\thid_hw_stop(hdev);\n\nEven after Window A is closed, hid_hw_close()/hid_hw_stop() still run\nafterwards, so a late \".event\" callback from the HID core (USB URB\ncompletion on real Apple hardware) can arrive after\ntimer_delete_sync() drained the softirq but before put_device() drops\nthe reference.  That callback reaches reset_inactivity_timer(), which\ncalls mod_timer() and re-arms the timer.  The freshly re-armed timer\ncan then fire on the about-to-be-freed backlight_device.\n\nBoth windows produce the same KASAN slab-use-after-free:\n\n  BUG: KASAN: slab-use-after-free in __mutex_lock+0x1aab/0x21c0\n  Read of size 8 at addr ffff88803ee9a108 by task swapper/0/0\n  Call Trace:\n   \u003cIRQ\u003e\n   __mutex_lock\n   backlight_device_set_brightness\n   appletb_inactivity_timer\n   call_timer_fn\n   run_timer_softirq\n   handle_softirqs\n  Allocated by task N:\n   devm_backlight_device_register\n   appletb_bl_probe\n  Freed by task M:\n   (concurrent hid_appletb_bl unbind path)\n\nClose both windows at once by reworking the tear-down in\nappletb_kbd_remove() and in the probe close_hw error path so that\n\n 1) hid_hw_close()/hid_hw_stop() run before the backlight cleanup,\n    guaranteeing no further .event callback can fire and re-arm the\n    timer, and\n 2) inside the \"if (kbd-\u003ebacklight_dev)\" block, timer_delete_sync()\n    runs before put_device(), so the softirq is drained before the\n    final reference is dropped."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-28T09:40:30.429Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/59a79938ca5541fe55d675304116b7ea684afef0"
        },
        {
          "url": "https://git.kernel.org/stable/c/93d989e47bc316c793a69c6a332e053c90e29f02"
        },
        {
          "url": "https://git.kernel.org/stable/c/4db2af929279c799b5653a39eb0795c72baffca4"
        }
      ],
      "title": "HID: appletb-kbd: fix UAF in inactivity-timer cleanup path",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-46213",
    "datePublished": "2026-05-28T09:40:30.429Z",
    "dateReserved": "2026-05-13T15:03:33.105Z",
    "dateUpdated": "2026-05-28T09:40:30.429Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

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GHSA-GMVX-6PFP-7MCV

CVE-2026-46213 (GCVE-0-2026-46213)

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Sightings

Nomenclature