CVE-2026-98688
In the Linux kernel, the following vulnerability has been resolved:
thunderbolt: Fix NULL dereference in tb_remove_work()
There is a slight race between tb_remove_work() and tb_domain_remove() which leads to dereferencing a NULL tb->root_switch pointer inside tb_free_unplugged_xdomains():
Commit a8937f35cf39 ("thunderbolt: Remove XDomain from the bus without holding tb->lock") doesn't seem right to move tb_free_unplugged_xdomains() out of the &tb->lock section and the check for tb->root_switch, in particular. It states:
tb_free_unplugged_xdomains() belongs to the former group of functions requiring the lock. And it also calls tb_xdomain_remove() which should only be called with &tb->lock held.
Read full descriptionShow less
Found by Linux Verification Center (linuxtesting.org) with Svace static analysis tool.
Technical details traces, logs and code from the original report
Thread A Thread B
tb_remove_work()
tb_domain_remove()
mutex_lock(&tb->lock)
tb_stop()
/* doesn't cancel a running callback */
cancel_delayed_work(&tcm->remove_work)
...
tb_switch_remove(tb->root_switch)
tb->root_switch = NULL
mutex_unlock(&tb->lock)
mutex_lock(&tb->lock)
...
/* without checking ->root_switch */
tb_free_unplugged_xdomains(tb->root_switch)
mutex_unlock(&tb->lock)
For this reason separate removing the XDomain from the topology data
structures (where we need the lock) from unregistering the device from
the bus (where remove callbacks of the drivers are being called).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
- 0.15 %
- 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
Raw JSON (NVD)
Show
{
"id": "CVE-2026-98688",
"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": "a8937f35cf39c39c64325aa84d0463d866850857",
"lessThan": "2f4cd43faa9d6470b30a9fbcbac6584db8108c1f",
"versionType": "git"
},
{
"status": "affected",
"version": "a8937f35cf39c39c64325aa84d0463d866850857",
"lessThan": "4310c6b8e75d6a47f7548e5948fbe6318aa4440a",
"versionType": "git"
},
{
"status": "affected",
"version": "3e9e823810b9a51f0bee9ed6e3d90df70484ff8d",
"versionType": "git"
},
{
"status": "affected",
"version": "9363cd4977260bf7f211feee54f85858bba2320c",
"versionType": "git"
},
{
"status": "affected",
"version": "5.10.266",
"lessThan": "5.11",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.15.217",
"lessThan": "5.16",
"versionType": "semver"
}
],
"programFiles": [
"drivers/thunderbolt/tb.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "7.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "7.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/thunderbolt/tb.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-10-18T16:17:22.207",
"references": [
{
"url": "https://git.kernel.org/stable/c/2f4cd43faa9d6470b30a9fbcbac6584db8108c1f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/4310c6b8e75d6a47f7548e5948fbe6318aa4440a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: Fix NULL dereference in tb_remove_work()\n\nThere is a slight race between tb_remove_work() and tb_domain_remove()\nwhich leads to dereferencing a NULL tb->root_switch pointer inside\ntb_free_unplugged_xdomains():\n\n Thread A Thread B\n\n tb_remove_work()\n tb_domain_remove()\n mutex_lock(&tb->lock)\n tb_stop()\n /* doesn't cancel a running callback */\n cancel_delayed_work(&tcm->remove_work)\n ...\n tb_switch_remove(tb->root_switch)\n tb->root_switch = NULL\n mutex_unlock(&tb->lock)\n mutex_lock(&tb->lock)\n ...\n /* without checking ->root_switch */\n tb_free_unplugged_xdomains(tb->root_switch)\n mutex_unlock(&tb->lock)\n\nCommit a8937f35cf39 (\"thunderbolt: Remove XDomain from the bus without\nholding tb->lock\") doesn't seem right to move tb_free_unplugged_xdomains()\nout of the &tb->lock section and the check for tb->root_switch, in\nparticular. It states:\n\n For this reason separate removing the XDomain from the topology data\n structures (where we need the lock) from unregistering the device from\n the bus (where remove callbacks of the drivers are being called).\n\ntb_free_unplugged_xdomains() belongs to the former group of functions\nrequiring the lock. And it also calls tb_xdomain_remove() which should\nonly be called with &tb->lock held.\n\nFound by Linux Verification Center (linuxtesting.org) with Svace static\nanalysis tool."
}
],
"lastModified": "2026-10-19T10:19:33.190",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}