PatchSiren cyber security CVE debrief
CVE-2026-53072 Linux CVE debrief
CVE-2026-53072 is a HIGH severity vulnerability in the Linux kernel's Bluetooth component. The vulnerability is caused by a locking issue in the hci_conn_request_evt() function when the HCI_PROTO_DEFER protocol is set. This can lead to a use-after-free (UAF) vulnerability if the connection is deleted concurrently. The vulnerability has a CVSS score of 8.8 and is considered HIGH severity. The issue is resolved by holding the lock in the hci_conn_request_evt() function.
- Vendor
- Linux
- Product
- Unknown
- CVSS
- HIGH 8.8
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-06-24
- Original CVE updated
- 2026-06-28
- Advisory published
- 2026-06-24
- Advisory updated
- 2026-06-28
Who should care
Linux kernel developers and maintainers, Bluetooth protocol implementers, and organizations using Linux-based systems with Bluetooth capabilities should be aware of this vulnerability. They should review their systems and apply patches or mitigations as needed to prevent exploitation.
Technical summary
The vulnerability is caused by a locking issue in the hci_conn_request_evt() function when the HCI_PROTO_DEFER protocol is set. Specifically, the function calls hci_connect_cfm(conn) without holding the hdev->lock. This can lead to a use-after-free (UAF) vulnerability if the connection is deleted concurrently. The issue is resolved by holding the lock in the hci_conn_request_evt() function. Only SCO and ISO protocols set HCI_PROTO_DEFER, and only for defer setup listen. HCI_EV_CONN_REQUEST is not generated for ISO.
Defensive priority
High priority should be given to patching or mitigating this vulnerability, as it has a high CVSS score and could be exploited to gain unauthorized access to sensitive information or disrupt system operations.
Recommended defensive actions
- Review and apply patches or updates to the Linux kernel to fix the locking issue in the hci_conn_request_evt() function.
- Implement additional monitoring and logging to detect potential exploitation attempts.
- Review system configurations and ensure that Bluetooth is only enabled when necessary.
- Consider implementing compensating controls, such as firewall rules or access controls, to limit the attack surface.
- Verify that system backups and incident response plans are up-to-date and effective.
Evidence notes
The CVE record and NVD detail provide information on the vulnerability, including its CVSS score and severity. The source item URL provides additional information on the vulnerability, including references to kernel.org stable commits.
Official resources
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CVE-2026-53072 CVE record
CVE.org
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CVE-2026-53072 NVD detail
NVD
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Source item URL
nvd_modified
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
This article is AI-assisted and based on the supplied source corpus.