CVE-2026-89668: Linux kernel · nfsd: move nfsd_debugfs_init() after nfsd4_init_slabs() in init_nfsd()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 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.
AI-suggested
A fix is available that reorders the initialization and cleanup functions in the Linux kernel nfsd component to prevent orphan debugfs files. Users should apply the updated kernel versions that include this fix. No additional mitigation is required beyond applying the official patch.
Description
A vulnerability in the Linux kernel's NFS daemon (nfsd) initialization sequence could lead to orphan debugfs files with stale function pointers if slab allocation fails. This occurs because nfsd_debugfs_init() runs before nfsd4_init_slabs(), and an early return bypasses cleanup. The issue has been resolved by reordering initialization and cleanup calls to prevent stale debugfs state.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89668 (opens in a new tab)
- git.kernel.org/stable/c/2c390c8a1764d67095fe444401861fac4c049362 (opens in a new tab)
- git.kernel.org/stable/c/4ae5d7490ae6a7b83b3d607f88c499f4f85e753a (opens in a new tab)
- git.kernel.org/stable/c/ab43ff94f5dfc2b6a080b167b69855eb7655c98b (opens in a new tab)
- ubuntu.com/security/CVE-2026-89668 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89668 (opens in a new tab)
- git.kernel.org/linus/2c390c8a1764d67095fe444401861fac4c049362 (opens in a new tab)