Bluetooth: SCO: serialise sco_conn lifetime against sco_recv_scodata()

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-99011
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-10-23 13:17:23 UTC
Updated2026-10-24 14:16:52 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: serialise sco_conn lifetime against sco_recv_scodata() sco_recv_scodata() upgrades the weak hcon->sco_data back-pointer to a strong reference under hdev->lock: hci_dev_lock(hdev); hcon = hci_conn_hash_lookup_handle(hdev, handle); ... conn = sco_conn_hold_unless_zero(hcon->sco_data); hci_dev_unlock(hdev); but the pointer is cleared from the other side without that lock. When the last sco_conn reference is dropped, sco_conn_free() ran conn->hcon->sco_data = NULL; with no hdev->lock held, so the RX path could read hcon->sco_data and call kref_get_unless_zero() on an sco_conn that was concurrently freed: BUG: KASAN: slab-use-after-free in sco_conn_hold_unless_zero+0xbe/0x160 Write of size 4 by task kworker/u17:0 Workqueue: hci0 hci_rx_work Call Trace: sco_conn_hold_unless_zero+0xbe/0x160 sco_recv_scodata+0x13f/0x490 hci_rx_work+0x3af/0x730 kref_get_unless_zero() only guards against a zero refcount, not against the backing memory already being freed. Give hcon->sco_data an actual reference on the sco_conn it points to, so the object cannot be freed while the pointer is still installed, and only clear and drop it from sco_conn_del(), which runs under hdev->lock (its callers, sco_connect_cfm() and sco_disconn_cfm(), hold it). The reader in sco_recv_scodata() also takes hdev->lock, so the store and the read are now serialised: the RX path either observes NULL or a reference that is guaranteed to stay valid until it drops its own. sco_conn_add() no longer hands its kref_init() reference to the caller as the connection's only reference; that initial reference is the one owned by hcon->sco_data, and callers get their own via sco_conn_hold(). Because the sco_conn can now outlive the socket (the association keeps it alive until the link goes down), the hci_conn can no longer be dropped from sco_conn_free() without regressing socket close: closing a connected SCO socket must still tear the link down. Move hci_conn ownership to the socket instead: __sco_chan_add() takes an hci_conn reference and it is released from sco_chan_del() and sco_sock_destruct(), exactly once. The sco_conn no longer owns an hci_conn reference, so sco_conn_add() stops consuming one and sco_connect() drops the hci_connect_sco() reference on every path; sco_connect_cfm() no longer needs its hci_conn_hold() dance.

Risk And Classification

Primary CVSS: v3.1 7.1 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67

CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

VersionSourceTypeScoreSeverityVector
3.1416baaa9-dc9f-4396-8d5f-8c081fb06d67Secondary7.1HIGHCVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
3.1CNADECLARED7.1HIGHCVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS v3.1 Breakdown

Attack Vector
Adjacent
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected e6720779ae612a14ac4ba7fe4fd5b27d900d932c b108ea7ebba147465f4158d8133f0e8f013762ed git Not specified
CNA Linux Linux affected e6720779ae612a14ac4ba7fe4fd5b27d900d932c 8a98d58f6cfe70d51138cd9ce894e72671d95f8a git Not specified
CNA Linux Linux affected e6720779ae612a14ac4ba7fe4fd5b27d900d932c 816fb1590a4c8cf8d05cd076057616be02e276f0 git Not specified
CNA Linux Linux affected 6.13 Not specified
CNA Linux Linux unaffected 6.13 semver Not specified
CNA Linux Linux unaffected 6.18.57 6.18.* semver Not specified
CNA Linux Linux unaffected 7.2.11 7.2.* semver Not specified
CNA Linux Linux unaffected 7.3 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/8a98d58f6cfe70d51138cd9ce894e72671d95f8a 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/816fb1590a4c8cf8d05cd076057616be02e276f0 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/b108ea7ebba147465f4158d8133f0e8f013762ed 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report