CVE-2026-53364 Linux CVE debrief

Who should care

Linux kernel developers and maintainers, Bluetooth protocol experts, and organizations using Linux-based systems with Bluetooth capabilities should be aware of this vulnerability. They should review and update the Linux kernel Bluetooth hci_conn component code to ensure proper memory management and verify and validate memory allocation and deallocation in the hci_le_big_terminate() function.

Technical summary

The hci_le_big_terminate() function in the Linux kernel's Bluetooth hci_conn component allocates memory using kzalloc_obj but does not free it when neither pa_sync_term nor big_sync_term flags are set after evaluating the PA and BIG sync connection state. This early-return path was introduced during refactoring of hci_le_big_terminate() to take struct hci_conn instead of raw u8 parameters, adding PA/BIG flag evaluation logic. The existing kfree() on hci_cmd_sync_queue failure does not cover this path. The vulnerability has been resolved, but the specific details of the vulnerability and its impact are not publicly available.

Defensive priority

Medium

Recommended defensive actions

• Review and update Linux kernel Bluetooth hci_conn component code to ensure proper memory management
• Verify and validate memory allocation and deallocation in hci_le_big_terminate() function
• Consider implementing additional monitoring and logging to detect potential memory leaks
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record was published on 2026-07-13T18:16:28.297Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the official CVE record. The Linux kernel's Bluetooth hci_conn component is affected, and the vulnerability has been resolved. However, the specific details of the vulnerability and its impact are not publicly available, and further verification is necessary.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.