CVE-2026-43255

Local service interruption via active URB resubmission

Published May 6, 2026 · Updated May 6, 2026

Race condition in the Linux kernel's Libertas USB Wi-Fi driver allows local users to interrupt service during firmware loading. usb_tx_block() resubmits cardp->tx_urb without waiting for an earlier transfer to finish, so usb_submit_urb() detects an active URB and triggers a kernel warning. Reachability requires the Libertas USB driver and overlapping transmissions, such as rapid firmware loading; the documented consequence is an availability interruption, not data access or modification.

CVSS severity5.5
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Race condition in the Linux kernel's Libertas USB Wi-Fi driver allows local users to interrupt service during firmware loading. usb_tx_block() resubmits cardp->tx_urb without waiting for an earlier transfer to finish, so usb_submit_urb() detects an active URB and triggers a kernel warning. Reachability requires the Libertas USB driver and overlapping transmissions, such as rapid firmware loading; the documented consequence is an availability interruption, not data access or modification.

The record

CVE
CVE-2026-43255
Published
May 6, 2026
Updated
May 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 6, 2026CVE publishedPublication date reported by the CVE source.
  2. May 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2902a9b4415a6bafc9b1e5dd360f065d757a0bb7
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3308c7504e093b22e91a4468470309cee2e26b83
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <498525d8358d6d20918787e59736d5b6a021e9fd
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5bfb25495e391a1be0db94b15715174fa06b93a1
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <948a39c95d0f8d73722910f8cdb7b6e3e9206232
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b82073564373e68c6ae3a96039fae14cd002a496
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d66676e6ca96bf8680f869a9bd6573b26c634622
  8. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fc188b44547dea4e7350833171982a6312befde9

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2902a9b4415a6bafc9b1e5dd360f065d757a0bb7; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3308c7504e093b22e91a4468470309cee2e26b83; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <498525d8358d6d20918787e59736d5b6a021e9fd; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5bfb25495e391a1be0db94b15715174fa06b93a1; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <948a39c95d0f8d73722910f8cdb7b6e3e9206232; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b82073564373e68c6ae3a96039fae14cd002a496; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d66676e6ca96bf8680f869a9bd6573b26c634622; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fc188b44547dea4e7350833171982a6312befde9

Published CVSS scores

5.5NIST National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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