# Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close

CVE record · `CVE-2026-63974`

- **Identifiers:** `CVE-2026-63974`
- **State:** Confirmed
- **Severity:** CVSS 8.8 High
- **Critical:** No
- **CNA:** Linux
- **Weakness (CWE):** [CWE-400](https://cwe.mitre.org/data/definitions/400.html)
- **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md)
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 19 Jul 2026
- **Updated:** 30 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 19 Jul 2026, 14:55 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

## Affected products, as the CNA wrote them

- Vendor: Linux. Product: Linux.
  - affected: `877afadad2dce8aae1f2aad8ce47e072d4f6165e to before ccf07dfb9d7d1e2c7a1eeb782f90d9b614ebba9c` (git)
  - affected: `877afadad2dce8aae1f2aad8ce47e072d4f6165e to before 7b81c1378b79c3143ca3fdb3d18ac0f01cbabb21` (git)
  - affected: `877afadad2dce8aae1f2aad8ce47e072d4f6165e to before 9cebe4680bb9a72f80c6541eb24af06db7a1fbc9` (git)
  - affected: `877afadad2dce8aae1f2aad8ce47e072d4f6165e to before 47330cc875b36a1cf7b3543cb2cf90a7c603ce0e` (git)
  - affected: `877afadad2dce8aae1f2aad8ce47e072d4f6165e to before 60bceb9a4c693e68cc90ba4b2dfb9e000e8638ff` (git)
  - affected: `877afadad2dce8aae1f2aad8ce47e072d4f6165e to before 525daaea459fc215f432de1b8debbd9144bf97b0` (git)
  - affected: `4bf367fa1fefabdf14938d0ac9ed60020389112e` (git)
  - affected: `3b382555706558f5c0587862b6dc03e96a252bba` (git)
  - affected: `5.18.18 to before 5.19` (semver)
  - affected: `5.19.2 to before 5.20` (semver)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `6.0`
  - unaffected: `before 6.0` (semver)
  - unaffected: `6.1.191 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.160 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.93 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.35 to 6.18.*, inclusive` (semver)
  - unaffected: `7.0.12 to 7.0.*, inclusive` (semver)
  - unaffected: `7.1 to *, inclusive` (original_commit_for_fix)
  - Other versions: affected

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> The Linux kernel is affected from version 6.0 until the fixes below. The source gives few details about how an attacker could reach this flaw or what impact it has. Upgrade to Linux kernel 6.1.191, 6.6.160, 6.12.93, or 6.18.35, or a later release in those series.

Written 12 Nov 2026.

## Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

## Severity and exploitation

- 8.8 High, CVSS 3.1: `CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`, from CNA (Linux)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0035, the 28th percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 19 Jul 2026, 16:17 UTC: [Confirmed by NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-63974)

## Sources

- [CVE List: CVE-2026-63974](https://www.cve.org/CVERecord?id=CVE-2026-63974)
- [NVD: CVE-2026-63974](https://nvd.nist.gov/vuln/detail/CVE-2026-63974)

### References from the CNA

- <https://git.kernel.org/stable/c/ccf07dfb9d7d1e2c7a1eeb782f90d9b614ebba9c>
- <https://git.kernel.org/stable/c/7b81c1378b79c3143ca3fdb3d18ac0f01cbabb21>
- <https://git.kernel.org/stable/c/9cebe4680bb9a72f80c6541eb24af06db7a1fbc9>
- <https://git.kernel.org/stable/c/47330cc875b36a1cf7b3543cb2cf90a7c603ce0e>
- <https://git.kernel.org/stable/c/60bceb9a4c693e68cc90ba4b2dfb9e000e8638ff>
- <https://git.kernel.org/stable/c/525daaea459fc215f432de1b8debbd9144bf97b0>

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.

## Check whether this affects you

This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it. Compare the affected versions above with what you run.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), `get_advisory` returns this record and `search_advisories` finds related ones. Setup: <https://agentprime.io/mcp.md>
- As JSON: <https://api.agentprime.io/v1/advisories/CVE-2026-63974>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-63974/>. Everything for agents: <https://agentprime.io/llms.txt>.