high · CVSS v3 7.1

CVE-2026-98633

CVE-2026-98633 is a high‑severity Linux kernel bug that leaks sk_buff objects during Bluetooth firmware dump processing when CONFIG_DEV_CORE

Overview

CVE-2026-98633 is a high‑severity Linux kernel bug that leaks sk_buff objects during Bluetooth firmware dump processing when CONFIG_DEV_COREDUMP is disabled. The leak can exhaust kernel memory and prevents recovery logic from running, potentially causing a denial of service. The issue affects the NXP Bluetooth driver (btnxpuart) and related firmware dump handling.

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btnxpuart: Fix skb leak in nxp_process_fw_dump() When CONFIG_DEV_COREDUMP=n, hci_devcd_append() returns -EOPNOTSUPP without freeing its skb argument. This leaks the cloned skb and also prevents nxp_set_ind_reset() from being called to perform recovery. Fix by guarding the hci_devcd_append(hdev, skb_clone(skb, GFP_ATOMIC)) call with IS_ENABLED(CONFIG_DEV_COREDUMP).

Impact

Confidentiality: no direct data exposure. Integrity: memory corruption could lead to kernel instability. Availability: potential memory exhaustion or crash, resulting in denial of service. Impacted parties: Linux kernel maintainers, embedded device operators using NXP Bluetooth modules, and system administrators managing affected devices.

Remediation

Apply the latest kernel patch that guards hci_devcd_append with IS_ENABLED(CONFIG_DEV_COREDUMP). If the patch is unavailable, enable CONFIG_DEV_COREDUMP in the kernel configuration or disable Bluetooth firmware dump functionality. After updating, monitor system memory usage for signs of skb leaks and verify that nxp_set_ind_reset() is invoked correctly.

Risk context

High severity with a CVSS v3 score of 7.1 indicates a significant risk of memory exhaustion and denial of service. Immediate patching or configuration mitigation is recommended to prevent potential availability impacts.

Affected products

  • Linux kernel
  • NXP Bluetooth driver
  • btnxpuart
  • Bluetooth firmware dump
  • CONFIG_DEV_COREDUMP

Scores

Severity
high
CVSS v2
2.1
CVSS v3
7.1
CVSS v4
—
EPSS
—

kernel bluetooth memory-leak high-severity NXP dev_coredump sk_buff

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