Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind (CVE-2026-90256) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-90256

Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind

Answer in brief

CVE-2026-90256 records a Unknown severity vulnerability in Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 17, 2026Updated Sep 17, 2026Source checked Sep 17, 2026First seen by HOL Sep 17, 2026Material review Sep 17, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=ab4eedb790cae44313759b50fe47da285e2519d5 <b495a3a9b33bc4e4613e685bf5c96c136caa22d8 \|\| >=ab4eedb790cae44313759b50fe47da285e2519d5 <2b66c83ff1751d6bd3201b3017206262ab46dc05 \|\| efc30877bd4bc85fefe98d80af60fafc86e5775e \|\| f87271d21dd4ee83857ca11b94e7b4952749bbae \|\| 18ab6b6078fa8191ca30a3065d57bf35d5635761 \|\| >=6.6.84 <6.7 \|\| >=6.12.20 <6.13 \|\| >=6.13.8 <6.14	b495a3a9b33bc4e4613e685bf5c96c136caa22d8, 2b66c83ff1751d6bd3201b3017206262ab46dc05, 6.7, 6.13, 6.14
Linux/Linuxgeneric	6.14	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to b495a3a9b33bc4e4613e685bf5c96c136caa22d8 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 17, 2026

Sources and claim methodology

Upstream source description

In 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.

Quoted source text, attributed separately from HOL analysis.