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.
Data as of 26 Oct 2026, 13:47 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation 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 adds proper error checking after nfsd4_acl_to_attr() in nfsd4_create(). Users should apply the updated Linux kernel versions that include this fix to ensure ACL translation errors are not ignored. No additional mitigation is indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's NFS server (nfsd) was resolved involving improper handling of ACL translation errors in the nfsd4_create() function. The function nfsd4_create() did not properly check the return value of nfsd4_acl_to_attr(), causing ACL translation errors to be silently discarded and the CREATE operation to proceed without applying the requested ACL. This issue has been fixed by adding an early exit check after nfsd4_acl_to_attr(), preventing the silent failure of ACL application.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89693 (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)
- 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)