CVE-2026-53072
CVE-2026-53072 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-667.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- EPSS exploit prediction: 0% (23rd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-38940
- Weakness: CWE-667
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER When protocol sets HCI_PROTO_DEFER, hci_conn_request_evt() calls hci_connect_cfm(conn) without hdev->lock. Generally hci_connect_cfm() assumes it is held, and if conn is deleted concurrently -> UAF. Only SCO and ISO set HCI_PROTO_DEFER and only for defer setup listen, and HCI_EV_CONN_REQUEST is not generated for ISO. In the non-deferred listening socket code paths, hci_connect_cfm(conn) is called with hdev->lock held. Fix by holding the lock.
Frequently asked questions
- What is CVE-2026-53072?
- In the Linux kernel, the following vulnerability has been resolved: Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER When protocol sets HCI_PROTO_DEFER, hci_conn_request_evt() calls hci_connect_cfm(conn) without hdev->lock. Generally hci_connect_cfm() assumes it is held, and if conn is deleted concurrently -> UAF. Only SCO and ISO set HCI_PROTO_DEFER and only for defer setup listen, and HCI_EV_CONN_REQUEST is not generated for ISO. In the non-deferred listening socket code paths, hci_connect_cfm(conn) is called with hdev->lock held. Fix by holding the lock.
- How severe is CVE-2026-53072?
- CVE-2026-53072 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-53072 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-53072?
- CVE-2026-53072 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-53072?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-53072 have an EU (EUVD) identifier?
- Yes. CVE-2026-53072 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38940.
- When was CVE-2026-53072 published?
- CVE-2026-53072 was published on 2026-06-24 and last updated on 2026-07-21.
References
- https://git.kernel.org/stable/c/385b2d0468a0871fc716c549fa3b0c257c7dbcb3
- https://git.kernel.org/stable/c/541d5bf9b5afaf41090b2a3aa7b47f2db2ff801f
- https://git.kernel.org/stable/c/5c7209a341ff2ac338b2b0375c34a307b37c9ac2
- https://git.kernel.org/stable/c/60e3f4ff02d1f2d55bfbf2ca32a97285a9771ee4
- https://git.kernel.org/stable/c/6b4d226d01ab7da0d2027a2a1e3a6079152e5065
- https://git.kernel.org/stable/c/9d4a6c0f43fc5e4d4f062e8e450e5483eb74176e
- https://git.kernel.org/stable/c/c27224daf0b08efbb2b24ed64b6139b294f5473a
- https://git.kernel.org/stable/c/c7777f534a8018ae4bb1c80d8925af4df588a314
Affected products (1)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
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