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CVE-2026-89683 (GCVE-0-2026-89683)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:46 – Updated: 2026-09-11 19:46
VLAI
Title
nfsd: fix dentry ref leak on V4ROOT export filehandle lookup
Summary
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.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 , < d493cf57f4c4dae5396cd6ad41e5c209d0615a81 (git)
Affected: ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 , < c1ae0f973bcba5730871e35976a0ab6878fdac34 (git)
Affected: ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 , < 11db8df188b34bdb8c6a3a0bf438e5fc8cd75aca (git)
Affected: ef7f6c4904d03ccd7478e1ac20ed75f79c4ac444 , < 6247023fbbec1325029f2d5f2a7cdc0f9f9ea15a (git)
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Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.109 , ≤ 6.12.* (semver)
Unaffected: 6.18.50 , ≤ 6.18.* (semver)
Unaffected: 7.2.4 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.