CVE-2026-23167: Linux kernel · nfc: nci: Fix race between rfkill and nci_unregister_device().
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 4.7 Medium · fixed in 5.15.0-1105.112~20.04.1 : 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 – fixed in 5.15.0-1105.112~20.04.1, 5.15.0-1110.119~20.04.1, 5.15.0-1106.115~20.04.1 +59
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 14 Feb 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
Upgrade to a fixed release listed under Affected software.
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 patch is available and should be applied to affected Linux kernel versions. The fix reorders rfkill device unregistration to occur before destroying the command workqueue, preventing use-after-free conditions. Users should update their Linux kernel to a version including this fix. No additional mitigation is required beyond applying the official patch.
Description
A race condition vulnerability in the Linux kernel's NFC subsystem (CVE-2026-23167) was resolved. The issue involved a race between rfkill and nci_unregister_device() leading to use-after-free conditions. This could cause kernel crashes due to improper ordering of device unregistration and resource cleanup. The fix reorders rfkill device unregistration to occur before destroying command workqueues, preventing access to freed memory. The vulnerability has a medium severity score and affects specific Linux kernel versions. A patch is available and should be applied to mitigate the issue.
References
- ubuntu.com/security/CVE-2026-23167 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23167 (opens in a new tab)
- git.kernel.org/linus/d2492688bb9fed6ab6e313682c387ae71a66ebae (opens in a new tab)
- git.kernel.org/stable/c/126cd30cad37bc7c2c85fe2df2a522d4edf0a5c5 (opens in a new tab)
- git.kernel.org/stable/c/546eba0b10989de9ccc7fd619e874a30561e2b88 (opens in a new tab)
- git.kernel.org/stable/c/8ea4d96419fb20f15a52ce657d49f1e7c91eb7ac (opens in a new tab)
- git.kernel.org/stable/c/c3369fc5e6120a72169e71acd72e987907a682af (opens in a new tab)
- git.kernel.org/stable/c/cd4412d5905ee580e96c48360dc98fcd9e6f3208 (opens in a new tab)
- git.kernel.org/stable/c/d2492688bb9fed6ab6e313682c387ae71a66ebae (opens in a new tab)
- git.kernel.org/stable/c/eaa5da5130deda26420273d4610cf6e4f794ed75 (opens in a new tab)
- ubuntu.com/security/notices/USN-8162-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8186-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8187-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8188-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8243-1 (opens in a new tab)