CVE-2026-23420: Linux kernel · wifi: wlcore: Fix a locking bug
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · patch available : update Linux kernel when convenient.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.09% chance of exploitation in 30 days – higher than 0% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 3 Apr 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 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1018.18?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A vendor-provided patch is available and should be applied to affected Linux kernel versions to resolve the locking bug in the wlcore driver. Users should update to the fixed kernel versions as per the Ubuntu Security Notice USN-8567-1. No additional mitigation actions are indicated by the vendor advisory.
Description
A locking bug in the Linux kernel's wlcore WiFi driver was fixed to ensure the mutex wl->mutex is properly locked before unlocking. This issue was detected by the Clang thread-safety analyzer and affects multiple specific Linux kernel versions. The vulnerability has a medium severity score and could impact system stability or availability due to improper locking. A patch is available to address this issue.
References
- ubuntu.com/security/CVE-2026-23420 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23420 (opens in a new tab)
- git.kernel.org/linus/72c6df8f284b3a49812ce2ac136727ace70acc7c (opens in a new tab)
- git.kernel.org/stable/c/1a1c28a08d74716f3f8e3a21c86b30d0ff13521a (opens in a new tab)
- git.kernel.org/stable/c/5feeea59ed142e15c3284d0b1a364c6786bf3487 (opens in a new tab)
- git.kernel.org/stable/c/72c6df8f284b3a49812ce2ac136727ace70acc7c (opens in a new tab)
- git.kernel.org/stable/c/7ab511003c5ae3bf5364d7699a2e3ab1db513680 (opens in a new tab)
- git.kernel.org/stable/c/aca4c9e4901b01b8b985993dc7df80bd1d1338bd (opens in a new tab)
- git.kernel.org/stable/c/fcef983ad88832f3aa83491a174c345de57afbbd (opens in a new tab)
- ubuntu.com/security/notices/USN-8567-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8597-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-2 (opens in a new tab)