CVE-2026-53072

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.

CVSS v3.1 Score

8.8

HIGH

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

EPSS — Exploit Prediction

0.0025

Probability of exploitation

0.16%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other 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

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. It has a CVSS v3.1 base score of 8.8 (HIGH).

How severe is CVE-2026-53072? +

CVE-2026-53072 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-53072? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.