---
id: CVE-2026-43255
title: 'wifi: libertas: fix WARNING in usb_tx_block'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: libertas: fix WARNING in usb_tx_block

  The function usb_tx_block() submits cardp->tx_urb without ensuring that
  any previous transmission on this URB has completed…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    498525d8358d6d20918787e59736d5b6a021e9fd
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    2902a9b4415a6bafc9b1e5dd360f065d757a0bb7
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    948a39c95d0f8d73722910f8cdb7b6e3e9206232
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    5bfb25495e391a1be0db94b15715174fa06b93a1
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    b82073564373e68c6ae3a96039fae14cd002a496
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    3308c7504e093b22e91a4468470309cee2e26b83
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    fc188b44547dea4e7350833171982a6312befde9
  - >-
    Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 <
    d66676e6ca96bf8680f869a9bd6573b26c634622
  - Linux 2.6.22
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T15:31:33.518669Z'
published: '2026-05-06'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T15:32:37.530Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-43255'
references:
  - url: 'https://git.kernel.org/stable/c/498525d8358d6d20918787e59736d5b6a021e9fd'
  - url: 'https://git.kernel.org/stable/c/2902a9b4415a6bafc9b1e5dd360f065d757a0bb7'
  - url: 'https://git.kernel.org/stable/c/948a39c95d0f8d73722910f8cdb7b6e3e9206232'
  - url: 'https://git.kernel.org/stable/c/5bfb25495e391a1be0db94b15715174fa06b93a1'
  - url: 'https://git.kernel.org/stable/c/b82073564373e68c6ae3a96039fae14cd002a496'
  - url: 'https://git.kernel.org/stable/c/3308c7504e093b22e91a4468470309cee2e26b83'
  - url: 'https://git.kernel.org/stable/c/fc188b44547dea4e7350833171982a6312befde9'
  - url: 'https://git.kernel.org/stable/c/d66676e6ca96bf8680f869a9bd6573b26c634622'
tags:
  - cve.org
epss: 0.00128
epssPercentile: 0.02475
ingestedAt: '2026-11-06T15:54:04.003Z'
---

## Overview

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

wifi: libertas: fix WARNING in usb_tx_block

The function usb_tx_block() submits cardp->tx_urb without ensuring that
any previous transmission on this URB has completed. If a second call
occurs while the URB is still active (e.g. during rapid firmware loading),
usb_submit_urb() detects the active state and triggers a warning:
'URB submitted while active'.

Fix this by enforcing serialization: call usb_kill_urb() before
submitting the new request. This ensures the URB is idle and safe to reuse.

## Affected

- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < 498525d8358d6d20918787e59736d5b6a021e9fd`
- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < 2902a9b4415a6bafc9b1e5dd360f065d757a0bb7`
- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < 948a39c95d0f8d73722910f8cdb7b6e3e9206232`
- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < 5bfb25495e391a1be0db94b15715174fa06b93a1`
- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < b82073564373e68c6ae3a96039fae14cd002a496`
- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < 3308c7504e093b22e91a4468470309cee2e26b83`
- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < fc188b44547dea4e7350833171982a6312befde9`
- `Linux >= 876c9d3aeb989cf1961f2c228d309ba5dcfb1172 < d66676e6ca96bf8680f869a9bd6573b26c634622`
- `Linux 2.6.22`

## Remediation

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