CVE-2026-89693: Linux kernel · nfsd: check nfsd4_acl_to_attr() return value in nfsd4_create()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.3 Medium.
Data as of 28 Oct 2026, 01:01 UTC
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NExploitation 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.
Description
In the Linux kernel, the following vulnerability has been resolved: nfsd: check nfsd4_acl_to_attr() return value in nfsd4_create() nfsd4_create() stores the return value of nfsd4_acl_to_attr() in status, but the switch(create->cr_type) block unconditionally overwrites it in every branch. ACL translation errors are silently discarded, and the CREATE proceeds without the requested ACL. Add an early exit check after nfsd4_acl_to_attr(), matching the pattern already used in nfsd4_setattr(). [ cel: prefer NFS4ERR_BADTYPE over NFS4ERR_ATTRNOTSUPP ]
References
- ubuntu.com/security/CVE-2026-89693 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89693 (opens in a new tab)
- git.kernel.org/linus/2c7912732184773dbd371a411da87af1cc080b86 (opens in a new tab)
- git.kernel.org/stable/c/2c7912732184773dbd371a411da87af1cc080b86 (opens in a new tab)
- git.kernel.org/stable/c/430ed49a16cf9ca249d0fb51490582090bc4848b (opens in a new tab)
- git.kernel.org/stable/c/80cebb0e8a8d1e758f0d671f5e047279c5c3e528 (opens in a new tab)