---
id: CVE-2026-93808
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ALSA: usb-audio: caiaq: validate EP1 reply lengths

  usb_ep1_command_reply_dispatch() uses buf[0] as a command byte and then
  reads command-specific fixed items from the …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ALSA: usb-audio: caiaq: validate EP1 reply lengths

  usb_ep1_command_reply_dispatch() uses buf[0] as a command byte and then
  reads command-specific fixed items from the …
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    af8a172c4f71ac30d625f2966d2389a7fa872819
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    74f3c639f64fa5da4e1613149798b5089bce2807
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    aba30af07d4fe499b50209801eba9da8a815522f
  - Linux < 6.12.111
  - Linux < 6.18.53
  - Linux (all versions)
published: '2026-09-24'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T13:17:21.670'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-93808'
references:
  - url: 'https://git.kernel.org/stable/c/74f3c639f64fa5da4e1613149798b5089bce2807'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/aba30af07d4fe499b50209801eba9da8a815522f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/af8a172c4f71ac30d625f2966d2389a7fa872819'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-24T16:47:15.896Z'
---

## Overview

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

ALSA: usb-audio: caiaq: validate EP1 reply lengths

usb_ep1_command_reply_dispatch() uses buf[0] as a command byte and then
reads command-specific fixed items from the same URB buffer. Several
paths use buf + 1, buf[1], buf[2], or buf + 3 without first proving that
urb->actual_length contains those bytes.

Add per-command length checks, use a payload length derived from the
bytes after the command byte for the control-state copy, and reject short
analog input payloads before the input helper reads fixed offsets from
the EP1 reply.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.