Description
In the Linux kernel, the following vulnerability has been resolved:

ALSA: FCP: Fix NULL pointer dereference in interface lookup

A malformed USB device can provide a vendor-specific interface without
any endpoint descriptors. fcp_find_fc_interface() currently selects the
first vendor-specific interface and reads endpoint 0 from it, without
checking whether the interface actually has any endpoints.

When bNumEndpoints is zero, no endpoint array is allocated for the parsed
alternate setting, so get_endpoint(..., 0) yields an invalid endpoint
descriptor pointer. Dereferencing it through usb_endpoint_num() then
triggers a NULL pointer dereference.

Skip vendor-specific interfaces that do not have any endpoints.
Published: 2026-08-15
Score: n/a
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

A malformed USB device can advertise a vendor‑specific interface without any endpoint descriptors. The ALSA FCP subsystem in the Linux kernel parses the device, selects the first vendor‑specific interface and then attempts to read endpoint 0. Because the interface declares zero endpoints, no endpoint array is allocated and the call to usb_endpoint_num() dereferences a NULL pointer, causing a kernel oops that crashes the system. The weakness is a classic NULL pointer dereference (CWE‑476).

Affected Systems

All Linux kernel versions that contain the ALSA FCP driver prior to the fix commit (c3ab06151ffcb8c3aeb8f78508658b6c0f05be932). The vulnerability affects the Linux Kernel as a whole, regardless of distribution, for any kernel that has not yet been updated to the patched version.

Risk and Exploitability

The flaw results in a clear denial‑of‑service and would be exploitable on any host that processes a malicious USB device. The EPSS score is not available and the vulnerability is not listed in CISA’s KEV catalog, indicating that no widespread public exploits are currently known. However, the attack can be performed with physical or firmware-level access to a USB port, making it highly feasible in environments that allow arbitrary USB devices to be attached.

Generated by OpenCVE AI on August 15, 2026 at 11:13 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Update the Linux kernel to a version that includes the patch commit 3ab06151ffcb8c3aeb8f78508658b6c0f05be932 or later.
  • Reboot the system after the kernel update to ensure the fixed code is loaded.
  • If an immediate kernel upgrade is not possible, disable the ALSA FCP subsystem or prevent the system from mounting USB devices by unbinding the relevant USB controller module.

Generated by OpenCVE AI on August 15, 2026 at 11:13 UTC.

Tracking

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Advisories

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History

Sat, 15 Aug 2026 11:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-476

Sat, 15 Aug 2026 06:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ALSA: FCP: Fix NULL pointer dereference in interface lookup A malformed USB device can provide a vendor-specific interface without any endpoint descriptors. fcp_find_fc_interface() currently selects the first vendor-specific interface and reads endpoint 0 from it, without checking whether the interface actually has any endpoints. When bNumEndpoints is zero, no endpoint array is allocated for the parsed alternate setting, so get_endpoint(..., 0) yields an invalid endpoint descriptor pointer. Dereferencing it through usb_endpoint_num() then triggers a NULL pointer dereference. Skip vendor-specific interfaces that do not have any endpoints.
Title ALSA: FCP: Fix NULL pointer dereference in interface lookup
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-15T05:56:27.464Z

Reserved: 2026-08-09T03:40:39.925Z

Link: CVE-2026-72403

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-15T06:22:13.870

Modified: 2026-08-15T06:22:13.870

Link: CVE-2026-72403

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-15T11:15:03Z

Weaknesses