CVE-2026-98859
In the Linux kernel, the following vulnerability has been resolved:
HID: multitouch: stop the release timer from being rearmed on remove
mt_remove() quiesces the sticky-finger timer before stopping the hardware:
timer_delete_sync() waits for a running callback and dequeues the timer, but it does not stop the timer from being armed again. The transport is still delivering reports at that point, and the report path rearms it:
A report that arrives after timer_delete_sync() has returned therefore leaves the timer queued. td is allocated with devm_kzalloc() against hdev->dev, so it is freed when the driver is unbound, after mt_remove() returns. When the timer fires afterwards, mt_expired_timeout() dereferences the freed td:
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Simply moving the teardown after hid_hw_stop() does not fix this on its own, because mt_expired_timeout() calls mt_release_contacts(), which walks hdev->inputs; the timer still has to be quiesced before hid_hw_stop() tears the input devices down.
Use timer_shutdown_sync() instead, which additionally makes any later mod_timer() a no-op, so neither ordering constraint has to be traded off against the other. This is the final-teardown pattern the function was introduced for, and hid-wiimote already uses it for the same reason.
Technical details traces, logs and code from the original report
timer_delete_sync(&td->release_timer);
sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);
hid_hw_stop(hdev);
if (app->quirks & MT_QUIRK_STICKY_FINGERS) {
if (td->mt_io_flags & MT_IO_SLOTS_MASK)
mod_timer(&td->release_timer,
jiffies + msecs_to_jiffies(100));
struct mt_device *td = timer_container_of(td, t, release_timer);
struct hid_device *hdev = td->hdev;
if (test_and_set_bit_lock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags))CVSS
NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days
- 0.16 %
- Percentile among all scored CVEs
- 4
- Score date
- 10/20/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
References
Show 4 references
Raw JSON (NVD)
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{
"id": "CVE-2026-98859",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4f4001bc76fd1a138a501fbd3d68cce72cbf96ce",
"lessThan": "1f1bd9a3117f082eb891c0986c4f0e04cd974c9a",
"versionType": "git"
},
{
"status": "affected",
"version": "4f4001bc76fd1a138a501fbd3d68cce72cbf96ce",
"lessThan": "0c19a6c1d25fd5ed66d1f80dc6f6e56cc1f0a787",
"versionType": "git"
},
{
"status": "affected",
"version": "4f4001bc76fd1a138a501fbd3d68cce72cbf96ce",
"lessThan": "a0125ca86e405b8a704e96157a6c10ca51087652",
"versionType": "git"
},
{
"status": "affected",
"version": "4f4001bc76fd1a138a501fbd3d68cce72cbf96ce",
"lessThan": "5acb2dace582f061aab5e14c399ac9480315f44b",
"versionType": "git"
}
],
"programFiles": [
"drivers/hid/hid-multitouch.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.13"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.13",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.56",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/hid/hid-multitouch.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-10-18T16:17:40.363",
"references": [
{
"url": "https://git.kernel.org/stable/c/0c19a6c1d25fd5ed66d1f80dc6f6e56cc1f0a787",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/1f1bd9a3117f082eb891c0986c4f0e04cd974c9a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5acb2dace582f061aab5e14c399ac9480315f44b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a0125ca86e405b8a704e96157a6c10ca51087652",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nHID: multitouch: stop the release timer from being rearmed on remove\n\nmt_remove() quiesces the sticky-finger timer before stopping the\nhardware:\n\n timer_delete_sync(&td->release_timer);\n\n sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);\n hid_hw_stop(hdev);\n\ntimer_delete_sync() waits for a running callback and dequeues the timer,\nbut it does not stop the timer from being armed again. The transport is\nstill delivering reports at that point, and the report path rearms it:\n\n if (app->quirks & MT_QUIRK_STICKY_FINGERS) {\n if (td->mt_io_flags & MT_IO_SLOTS_MASK)\n mod_timer(&td->release_timer,\n jiffies + msecs_to_jiffies(100));\n\nA report that arrives after timer_delete_sync() has returned therefore\nleaves the timer queued. td is allocated with devm_kzalloc() against\nhdev->dev, so it is freed when the driver is unbound, after mt_remove()\nreturns. When the timer fires afterwards, mt_expired_timeout()\ndereferences the freed td:\n\n struct mt_device *td = timer_container_of(td, t, release_timer);\n struct hid_device *hdev = td->hdev;\n\n if (test_and_set_bit_lock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags))\n\nSimply moving the teardown after hid_hw_stop() does not fix this on its\nown, because mt_expired_timeout() calls mt_release_contacts(), which\nwalks hdev->inputs; the timer still has to be quiesced before\nhid_hw_stop() tears the input devices down.\n\nUse timer_shutdown_sync() instead, which additionally makes any later\nmod_timer() a no-op, so neither ordering constraint has to be traded off\nagainst the other. This is the final-teardown pattern the function was\nintroduced for, and hid-wiimote already uses it for the same reason."
}
],
"lastModified": "2026-10-19T10:19:49.980",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}