# CVE-2026-98423: wifi: mac80211_hwsim: don't hand frames to mac80211 while stopping

CVE-2026-98423 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-98423, released October 16, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-98423
- Priority: Routine
- CVSS: 1.9 (Low)
- EPSS: 0.0022
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 14, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98423

## Description

In the Linux kernel, the following vulnerability has been resolved:  wifi: mac80211_hwsim: don't hand frames to mac80211 while stopping  The code checks ->started for frames coming from wmediumd, but the radio can be stopped after the check and before frame delivery, causing mac80211 to hit the WARN_ON(!local->started).  Expand the mutex for this case and synchronise against it when the radio is stopped to avoid being able to hit the warning with hwsim.  Drop the error print that would've complicated the error path, it only triggers for allocation failures (already noisy) and malformed frames anyway.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 6.1.190-1 | [DEBIAN-CVE-2026-98423](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98423.md) | Oct 16, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.113-1 | [DEBIAN-CVE-2026-98423](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98423.md) | Oct 16, 2026 |
| Linux | linux Debian 14 | 7.2.8-1 | [DEBIAN-CVE-2026-98423](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98423.md) | Oct 16, 2026 |
| Linux | linux-6.12 Debian 12.15 (bookworm) | 6.12.113-1~deb12u1 | [DEBIAN-CVE-2026-98423](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98423.md) | Oct 16, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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