In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close Since… (CVE-2026-63974)
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close Since hci_dev_close_sync() can now be called during the reset path, we should also set HCI_CMD_DRAIN_WORKQUEUE. This avoids queuing timeouts while the hdev workqueue is being drained.
AI Analysis
Technical Summary
The Linux kernel Bluetooth subsystem had a vulnerability where the hci_dev_close_sync() function did not set the HCI_CMD_DRAIN_WORKQUEUE flag during device close operations. Since this function can be called during the reset path, the absence of this flag could lead to queuing timeouts while the device's workqueue was being drained. The vulnerability has been resolved by setting the HCI_CMD_DRAIN_WORKQUEUE flag appropriately during device close, preventing these timeouts.
Potential Impact
The vulnerability could cause queuing timeouts in the Bluetooth device workqueue during device close or reset operations, potentially leading to degraded Bluetooth functionality or instability. There is no indication of remote code execution or privilege escalation from the provided data.
Mitigation Recommendations
A fix has been implemented in the Linux kernel to set HCI_CMD_DRAIN_WORKQUEUE during device close, resolving the issue. Users should apply the official Linux kernel updates that include this fix. Patch status is not explicitly confirmed in the provided data; therefore, check the vendor or Linux kernel advisory for the exact fixed versions and update accordingly.
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close Since… (CVE-2026-63974)
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close Since hci_dev_close_sync() can now be called during the reset path, we should also set HCI_CMD_DRAIN_WORKQUEUE. This avoids queuing timeouts while the hdev workqueue is being drained.
CVSS v3.1
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Linux kernel Bluetooth subsystem had a vulnerability where the hci_dev_close_sync() function did not set the HCI_CMD_DRAIN_WORKQUEUE flag during device close operations. Since this function can be called during the reset path, the absence of this flag could lead to queuing timeouts while the device's workqueue was being drained. The vulnerability has been resolved by setting the HCI_CMD_DRAIN_WORKQUEUE flag appropriately during device close, preventing these timeouts.
Potential Impact
The vulnerability could cause queuing timeouts in the Bluetooth device workqueue during device close or reset operations, potentially leading to degraded Bluetooth functionality or instability. There is no indication of remote code execution or privilege escalation from the provided data.
Mitigation Recommendations
A fix has been implemented in the Linux kernel to set HCI_CMD_DRAIN_WORKQUEUE during device close, resolving the issue. Users should apply the official Linux kernel updates that include this fix. Patch status is not explicitly confirmed in the provided data; therefore, check the vendor or Linux kernel advisory for the exact fixed versions and update accordingly.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-7hr8-6q2g-wqfg
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-63974"]
- Ecosystems
- []
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a5d27aa2a4a8d598912e226
Added to database: 07/19/2026, 19:38:18 UTC
Last enriched: 07/19/2026, 20:02:31 UTC
Last updated: 07/20/2026, 21:51:55 UTC
Views: 10
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