Use-After-Free in Linux kernel (CVE-2026-64433)
Summary
Vulnerability in Linux kernel (CVE-2026-64433). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: Fix UAF of hci_conn_params in add_device_complete
add_device_complete() runs from the hci_cmd_sync_work kworker, which
holds only hci_req_sync_lock and not hci_dev_lock. It calls
hci_conn_params_lookup() and then dereferences the returned object
(params->flags) without taking hci_dev_lock:
params = hci_conn_params_lookup(hdev, &cp->addr.bdaddr,
le_addr_type(cp->addr.type));
...
device_flags_changed(NULL, hdev, &cp->addr.bdaddr,
cp->addr.type, hdev->conn_flags,
params ? params->flags : 0);
hci_conn_params_lookup() walks hdev->le_conn_params and is documented to
require hdev->lock. A concurrent MGMT_OP_REMOVE_DEVICE
(remove_device()), which does run under hci_dev_lock, can call
hci_conn_params_free() to list_del() and kfree() the very object the
lookup returned, so the subsequent params->flags read touches freed
memory [0].
Hold hci_dev_lock() across the hci_conn_params_lookup() and the read of
params->flags (and the matching event emission) so the lookup result
cannot be freed by a concurrent remove_device() before it is used,
honouring the locking contract of hci_conn_params_lookup().
[0]: (trailing page/memory-state dump trimmed)
BUG: KASAN: slab-use-after-free in add_device_complete+0x358/0x3d8 net/bluetooth/mgmt.c:7671
Read of size 1 at addr ffff000017ab26c1 by task kworker/u9:8/388
CPU: 1 UID: 0 PID: 388 Comm: kworker/u9:8 Not tainted 7.0.11 #20 PREEMPT…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-64433 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-64433" on the vendor's site.
CVE-2026-64433 (Linux kernel) — CWE-416 / CVSS v3 7.8
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Use-after-free (CWE-416) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-64433 linux-lts Fixed in: 6.12.103-r0
- Debian DEBIAN-CVE-2026-64433 linux Fixed in: 6.12.96-1
- Ubuntu UBUNTU-CVE-2026-64433 linux-hwe-edge
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com