What is CVE-2026-90408?

CVE-2026-90408 is a High severity Linux kernel vulnerability with a CVSS score of 7.7 out of 10, affecting Linux kernel versions from 6.3 onward and patched in 7.2.6 and 7.3-rc1. CVE-2026-90408 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-90408?

CVE-2026-90408 has a CVSS score of 7.7 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.

Is there a patch available for CVE-2026-90408?

Yes, CVE-2026-90408 has been patched. Fixed versions include 7.2.6 and 7.3-rc1. If you are running Linux kernel 6.3 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-90408 actively exploited?

CVE-2026-90408 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-90408

High

In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix overreads in ath12k_wmi_process_csa_switch_count_event() There is no policy entry for WMI_TAG_PDEV_CSA_SWITCH_COUNT_STATUS_EVENT, so the parse infrastructure does not enforce a minimum length for the event struct. Additionally, the num_vdevs field is taken directly from firmware and used as a loop bound over the vdev_ids array without checking that it fits within the TLV payload. Either condition can cause an out-of-bounds read. Add a TLV policy entry for WMI_TAG_PDEV_CSA_SWITCH_COUNT_STATUS_EVENT so the parse infrastructure enforces a minimum length for the fixed-size event struct. Add a helper ath12k_wmi_tlv_data_len() to recover the payload length of a parsed TLV from the header preceding its data pointer. Use it in ath12k_wmi_process_csa_switch_count_event() to bound num_vdevs before the loop. Compile tested only.

Package Linux Kernel

Published 2026-09-17

Last modified 2026-09-18

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.7

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Affected versions

Linux kernel versions 6.3 and later are affected. Fixed in 7.2.6, 7.3-rc1 and their respective stable series.

Affected from

≥ 6.3

Fixed in

✓ 7.2.6 7.2.x ✓ 7.3-rc1

References

2 total

Details

CVE ID CVE-2026-90408

Severity High

CVSS score 7.7 / 10

CVSS version 3.1

Published 2026-09-17

Modified 2026-09-18

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-90408?

CVE-2026-90408 is a High severity Linux kernel vulnerability with a CVSS score of 7.7 out of 10 . It affects Linux kernel versions from 6.3 onward and has been patched in 7.2.6 and 7.3-rc1. CVE-2026-90408 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-90408?

CVE-2026-90408 has a CVSS score of 7.7 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
Is there a patch available for CVE-2026-90408?

Yes. CVE-2026-90408 has been patched. Fixed versions include 7.2.6 and 7.3-rc1. If you are running Linux kernel 6.3 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-90408 actively exploited?

No. CVE-2026-90408 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.