GHSA-F7WF-GFQ3-CM8R
Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-15 06:32In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: 6lowpan: avoid untracked enable work
lowpan_enable_set() allocates a temporary work item and schedules do_enable_set() on system_wq, then returns to debugfs. The debugfs active operation has ended at that point, but the worker still executes module text and manipulates enable_6lowpan and listen_chan.
bt_6lowpan_exit() removes the debugfs files and immediately closes and puts listen_chan. It has no pointer to the queued work item, so it cannot cancel or flush it before tearing down the state that the worker uses.
The buggy scenario involves two paths, with each column showing the order within that path:
debugfs enable write module exit 1. lowpan_enable_set() allocates 1. bt_6lowpan_exit() removes set_enable work the debugfs file 2. schedule_work() queues 2. bt_6lowpan_exit() closes do_enable_set() and puts listen_chan 3. the write operation returns 3. module teardown can continue 4. do_enable_set() later runs against stale state
Run the enable state transition synchronously in lowpan_enable_set() instead. The simple debugfs setter can sleep, and this file already handles the 6LoWPAN control write synchronously under the same set_lock. Once the setter returns, debugfs removal covers the whole operation and exit can no longer race with an untracked work item.
Validation reproduced this kernel report: BUG: KASAN: slab-use-after-free in do_enable_set+0x113/0x2e0 Workqueue: events do_enable_set [bluetooth_6lowpan] The buggy address belongs to the object at ffff888109cb8000
{
"affected": [],
"aliases": [
"CVE-2026-72337"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-15T06:22:06Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: 6lowpan: avoid untracked enable work\n\nlowpan_enable_set() allocates a temporary work item and schedules\ndo_enable_set() on system_wq, then returns to debugfs. The debugfs active\noperation has ended at that point, but the worker still executes module\ntext and manipulates enable_6lowpan and listen_chan.\n\nbt_6lowpan_exit() removes the debugfs files and immediately closes and\nputs listen_chan. It has no pointer to the queued work item, so it cannot\ncancel or flush it before tearing down the state that the worker uses.\n\nThe buggy scenario involves two paths, with each column showing the order\nwithin that path:\n\ndebugfs enable write module exit\n1. lowpan_enable_set() allocates 1. bt_6lowpan_exit() removes\n set_enable work the debugfs file\n2. schedule_work() queues 2. bt_6lowpan_exit() closes\n do_enable_set() and puts listen_chan\n3. the write operation returns 3. module teardown can continue\n4. do_enable_set() later runs\n against stale state\n\nRun the enable state transition synchronously in lowpan_enable_set()\ninstead. The simple debugfs setter can sleep, and this file already handles\nthe 6LoWPAN control write synchronously under the same set_lock. Once the\nsetter returns, debugfs removal covers the whole operation and exit can no\nlonger race with an untracked work item.\n\nValidation reproduced this kernel report:\nBUG: KASAN: slab-use-after-free in do_enable_set+0x113/0x2e0\nWorkqueue: events do_enable_set [bluetooth_6lowpan]\nThe buggy address belongs to the object at ffff888109cb8000",
"id": "GHSA-f7wf-gfq3-cm8r",
"modified": "2026-08-15T06:32:21Z",
"published": "2026-08-15T06:32:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72337"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/352a59dc1f4a41314b6f827c17e16af7ca88271a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/feb3fc2c38ed52003142f31e04109719b200c049"
}
],
"schema_version": "1.4.0",
"severity": []
}
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.
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.