CVE-2026-98340: Linux kernel · wifi: cfg80211: only group hidden BSSes with beacon entries
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 28 Oct 2026, 01:28 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
Exploitation evidence
Disclosed: evidence found.
CVE published 6 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: only group hidden BSSes with beacon entries When a probe response for an unknown BSS comes in, __cfg80211_bss_update() looks for an existing entry with the same BSSID and a hidden (zero-length or NUL-filled) SSID, and if it finds one it groups them, using the beacon IEs from the existing entry. But that could find another entry without a beacon, if it was also from a probe response (with SSID), so there's a group without beacon elements. If a beacon with a hidden SSID for that BSSID arrives later, cfg80211_combine_bsses() goes looking for the probe response entries that belong to it - i.e. entries with the same BSSID and channel that have no beacon IEs - and finds those two. They are already grouped with each other, so it hits its WARN_ON_ONCE(bss->pub.hidden_beacon_bss) WARN_ON_ONCE(!list_empty(&bss->hidden_list)) which are there because an entry without beacon elements is not supposed to be part of a group yet. Only combine entries when a beacon was already received, ones that are kept separate will be combined when a beacon arrives.
References
- ubuntu.com/security/CVE-2026-98340 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98340 (opens in a new tab)
- git.kernel.org/linus/068843ed0902c552a13860c5ec6b2ca65b57a065 (opens in a new tab)
- git.kernel.org/stable/c/068843ed0902c552a13860c5ec6b2ca65b57a065 (opens in a new tab)
- git.kernel.org/stable/c/332ea1502c46f53375cb109fa82bfaff818f3a41 (opens in a new tab)
- git.kernel.org/stable/c/3658093df69849daf4f813a8f087f358e13be203 (opens in a new tab)
- git.kernel.org/stable/c/4cd6a518ce7527284bbc9baab5fa2453a7d477c2 (opens in a new tab)
- git.kernel.org/stable/c/73365b81630b57e1a1f9d50dc87281797855c2ac (opens in a new tab)
- git.kernel.org/stable/c/7405dd19bda4537a2843637d8d7bed1efd4776cf (opens in a new tab)
- git.kernel.org/stable/c/74ed0d992f392c75e1969415527e06df3f7a4034 (opens in a new tab)
- git.kernel.org/stable/c/86235be788094131912e9bd8412b358d91d99f49 (opens in a new tab)