CVE-2026-90344Hinoki check available

Firmware crash via ignored channel-zero switch announcements

Published Sep 17, 2026 · Updated Sep 17, 2026

Denial of service in Linux 6.9 mac80211 allows attackers to crash Intel Wi-Fi firmware via a channel-zero switch announcement. The CSA parser in net/mac80211/spectmgmt.c treats channel zero as absent information, ignoring the invalid announcement instead of disconnecting. Exposure requires an affected mac80211 client receiving that announcement from its access point; the reported consequence is an Intel device firmware crash, not a host kernel crash.

CVSS severity6.5
Medium
EPSS probability0.20%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Denial of service in Linux 6.9 mac80211 allows attackers to crash Intel Wi-Fi firmware via a channel-zero switch announcement. The CSA parser in net/mac80211/spectmgmt.c treats channel zero as absent information, ignoring the invalid announcement instead of disconnecting. Exposure requires an affected mac80211 client receiving that announcement from its access point; the reported consequence is an Intel device firmware crash, not a host kernel crash.

The record

CVE
CVE-2026-90344
Published
Sep 17, 2026
Updated
Sep 17, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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?

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  1. Affected versionversion=21c3f8f95554feff9bed15703e89adbe582e0383 <099aadb2012d7490bc584cc5075ef11cbc33f2c3
  2. Affected versionversion=21c3f8f95554feff9bed15703e89adbe582e0383 <cf57f0a674cc3e3cda1a789359cc1238b61b9d7d
  3. Affected versionversion=21c3f8f95554feff9bed15703e89adbe582e0383 <e7bc5ab93acd1c3f54feeb9fa19ead3530168090
  4. Affected versionversion=21c3f8f95554feff9bed15703e89adbe582e0383 <eef374088450bb91626e133c7172b8a0e969a522
  5. Affected versionversion=6.9

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=21c3f8f95554feff9bed15703e89adbe582e0383 <099aadb2012d7490bc584cc5075ef11cbc33f2c3; version=21c3f8f95554feff9bed15703e89adbe582e0383 <cf57f0a674cc3e3cda1a789359cc1238b61b9d7d; version=21c3f8f95554feff9bed15703e89adbe582e0383 <e7bc5ab93acd1c3f54feeb9fa19ead3530168090; version=21c3f8f95554feff9bed15703e89adbe582e0383 <eef374088450bb91626e133c7172b8a0e969a522; version=6.9

Published CVSS scores

6.5Amazon LinuxCVSS:3.1/AV:A/AC:L/PR:N/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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