CVE-2026-89683
nfsd: fix dentry ref leak on V4ROOT export filehandle lookup
Description
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix dentry ref leak on V4ROOT export filehandle lookup nfsd_set_fh_dentry() leaks the dentry reference from exportfs_decode_fh_raw() when the NFS3_FHSIZE or NFS_FHSIZE switch cases detect NFSEXP_V4ROOT and goto out. The out: label calls exp_put() but never dput(dentry), and fhp->fh_dentry was never assigned so fh_put() cannot compensate. A crafted NFSv3 filehandle targeting a V4ROOT export's fsid triggers the leak on every request.
INFO
Published Date :
Sept. 11, 2026, 8:19 p.m.
Last Modified :
Sept. 11, 2026, 8:19 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-89683
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Update the Linux kernel to a patched version.
- Verify the NFSv3 export configuration.
- Restart the NFS service.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-89683.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-89683 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-89683
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-89683 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-89683 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 11, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: nfsd: fix dentry ref leak on V4ROOT export filehandle lookup nfsd_set_fh_dentry() leaks the dentry reference from exportfs_decode_fh_raw() when the NFS3_FHSIZE or NFS_FHSIZE switch cases detect NFSEXP_V4ROOT and goto out. The out: label calls exp_put() but never dput(dentry), and fhp->fh_dentry was never assigned so fh_put() cannot compensate. A crafted NFSv3 filehandle targeting a V4ROOT export's fsid triggers the leak on every request. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89683.json">CVE-2026-89683</a> Added Reference https://git.kernel.org/stable/c/11db8df188b34bdb8c6a3a0bf438e5fc8cd75aca Added Reference https://git.kernel.org/stable/c/6247023fbbec1325029f2d5f2a7cdc0f9f9ea15a Added Reference https://git.kernel.org/stable/c/c1ae0f973bcba5730871e35976a0ab6878fdac34 Added Reference https://git.kernel.org/stable/c/d493cf57f4c4dae5396cd6ad41e5c209d0615a81