GHSA-323M-RJ3W-9JQP
Vulnerability from github – Published: 2026-09-17 18:31 – Updated: 2026-09-18 18:31In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind
hci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via hci_conn_timeout (disc_work) -> hci_proto_disconn_ind -> l2cap_disconn_ind. This is UAF if the l2cap_conn is deleted concurrently.
disc_work is disabled sync in hci_conn_del(), so we cannot take hci_dev_lock in disc_work.
Fix by using proto_lock to guard l2cap_data, in addition to hdev->lock which is held in other access paths.
{
"affected": [],
"aliases": [
"CVE-2026-90256"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-17T17:17:21Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind\n\nhci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via\nhci_conn_timeout (disc_work) -\u003e hci_proto_disconn_ind -\u003e\nl2cap_disconn_ind. This is UAF if the l2cap_conn is deleted\nconcurrently.\n\ndisc_work is disabled sync in hci_conn_del(), so we cannot take\nhci_dev_lock in disc_work.\n\nFix by using proto_lock to guard l2cap_data, in addition to hdev-\u003elock\nwhich is held in other access paths.",
"id": "GHSA-323m-rj3w-9jqp",
"modified": "2026-09-18T18:31:28Z",
"published": "2026-09-17T18:31:58Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90256"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2b66c83ff1751d6bd3201b3017206262ab46dc05"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b495a3a9b33bc4e4613e685bf5c96c136caa22d8"
}
],
"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 |
|---|
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.