GHSA-87C7-V43R-F3F4
Vulnerability from github – Published: 2026-08-15 15:30 – Updated: 2026-08-17 06:33In the Linux kernel, the following vulnerability has been resolved:
thunderbolt: Prevent XDomain delayed work use-after-free on disconnect
tb_xdp_handle_request() runs on system_wq and queues xd->state_work via queue_delayed_work() in three request handlers: PROPERTIES_CHANGED_REQUEST, UUID_REQUEST (via start_handshake), and LINK_STATE_CHANGE_REQUEST. Similarly, update_xdomain() queues xd->properties_changed_work when local properties change.
Concurrently, tb_xdomain_remove() calls stop_handshake() which does cancel_delayed_work_sync() on both delayed works. Later, tb_xdomain_unregister() calls device_unregister() which eventually frees the xdomain. Since commit 559c1e1e0134 ("thunderbolt: Run tb_xdp_handle_request() in system workqueue") moved the request handler off tb->wq, the handler and the remove path are no longer serialized. If queue_delayed_work() executes after cancel_delayed_work_sync() but before the xdomain is freed, the delayed work fires on a freed object.
Add xd->removing that tb_xdomain_remove() sets under xd->lock before calling stop_handshake(). Each external queue site holds the same lock and checks removing before calling queue_delayed_work(). This provides the mutual exclusion needed: either the queue site acquires the lock first and queues work that the subsequent cancel will see, or the remove path acquires the lock first and the queue site observes removing == true and skips the queue.
{
"affected": [],
"aliases": [
"CVE-2026-74575"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-15T13:18:03Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: Prevent XDomain delayed work use-after-free on disconnect\n\ntb_xdp_handle_request() runs on system_wq and queues\nxd-\u003estate_work via queue_delayed_work() in three request handlers:\nPROPERTIES_CHANGED_REQUEST, UUID_REQUEST (via start_handshake),\nand LINK_STATE_CHANGE_REQUEST. Similarly, update_xdomain() queues\nxd-\u003eproperties_changed_work when local properties change.\n\nConcurrently, tb_xdomain_remove() calls stop_handshake() which does\ncancel_delayed_work_sync() on both delayed works. Later,\ntb_xdomain_unregister() calls device_unregister() which eventually\nfrees the xdomain. Since commit 559c1e1e0134 (\"thunderbolt: Run\ntb_xdp_handle_request() in system workqueue\") moved the request\nhandler off tb-\u003ewq, the handler and the remove path are no longer\nserialized. If queue_delayed_work() executes after\ncancel_delayed_work_sync() but before the xdomain is freed, the\ndelayed work fires on a freed object.\n\nAdd xd-\u003eremoving that tb_xdomain_remove() sets under xd-\u003elock\nbefore calling stop_handshake(). Each external queue site holds\nthe same lock and checks removing before calling\nqueue_delayed_work(). This provides the mutual exclusion needed:\neither the queue site acquires the lock first and queues work that\nthe subsequent cancel will see, or the remove path acquires the\nlock first and the queue site observes removing == true and skips\nthe queue.",
"id": "GHSA-87c7-v43r-f3f4",
"modified": "2026-08-17T06:33:54Z",
"published": "2026-08-15T15:30:36Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74575"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2aa2cde2cc79a79d8ea4a15be9f4a67fc528ae91"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2c5d2d3c3f70cde2565d7b279b544893a2035842"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/33c0ee18cf8665c974b00f4e0ba769fbc07efe10"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/54a62153c765cd24239cde1f2633f2a2fd005368"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/91b40862a02000f490b63f1d315be3ee31e83871"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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- 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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.