---
id: CVE-2026-16147
title: >-
  The ITE IT82xx2 USB device-controller driver (drivers/usb/udc/udc_it82xx2.c)
  mishandles multi-packet OUT transfers on non-control endpoints
summary: >-
  The ITE IT82xx2 USB device-controller driver (drivers/usb/udc/udc_it82xx2.c)
  mishandles multi-packet OUT transfers on non-control endpoints. In
  work_handler_out() the active transfer buffer is obtained with udc_buf_peek()
  (which does not…
severity: medium
cvss: 6.8
cvssVector: 'CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
vendor: zephyrproject
product: zephyr
affected:
  - zephyr >= 4.0.0 < 4.4.2
published: '2026-09-14'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T21:10:41.650'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-16147'
references:
  - url: >-
      https://github.com/zephyrproject-rtos/zephyr/commit/2abc3088a6598579cf322452801a13cb0ec57b0e
    label: vulnerabilities@zephyrproject.org
  - url: >-
      https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-3q4g-7w6j-8qfp
    label: vulnerabilities@zephyrproject.org
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-14T20:04:57.852432Z'
ingestedAt: '2026-09-14T20:14:21.146Z'
epss: 0.00182
epssPercentile: 0.08024
---

## Overview

The ITE IT82xx2 USB device-controller driver (drivers/usb/udc/udc_it82xx2.c) mishandles multi-packet OUT transfers on non-control endpoints. In work_handler_out() the active transfer buffer is obtained with udc_buf_peek() (which does not dequeue it); when a full max-packet-size packet arrives but the buffer still has tailroom (the transfer is not yet complete), the pre-fix code both re-arms the endpoint to keep filling that same buf via work_handler_xfer_continue() and simultaneously hands the same, still-being-filled buffer to the upper stack with udc_submit_ep_event().

Because udc_submit_ep_event() transfers ownership of the buffer to the USB device stack (usbd_event_carrier() appends &buf->node to uds_ctx->ep_events, after which the class handler processes and net_buf_unref()s it), the driver continues to DMA subsequent host-controlled OUT packets into a buffer the upper stack may already have freed and recycled — a use-after-free write. In addition, since the buffer was never dequeued, the completing packet runs udc_buf_get() on the same object and submits it a second time, appending &buf->node to the event slist twice (singly-linked-list corruption) and causing a double net_buf_unref().

The IT82xx2 is a USB peripheral controller, so the untrusted USB host controls OUT-transfer packetization and can force this path against any non-control OUT endpoint whose queued buffer exceeds one packet — an ordinary bulk/interrupt pattern. The driver and USB device stack run in kernel context above the external host, giving the host a device-side kernel heap-corruption primitive: a reliable denial of service and, because the written bytes are attacker-controlled, plausible corruption of adjacent net_buf pool memory. The vector is physical (USB attach). The fix defers submission until the buffer is completely filled and lets xfer_work_handler() drive continuation, so each OUT buffer is submitted to the upper stack exactly once.

## Remediation

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