CVE-2026-53395 (GCVE-0-2026-53395)

Vulnerability from cvelistv5 – Published: 2026-07-19 12:01 – Updated: 2026-07-20 13:39
VLAI
Title
nfsd: fix dead ACL conflict guard in nfsd4_create
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix dead ACL conflict guard in nfsd4_create nfsd4_create() steals create->cr_dpacl/cr_pacl into the local nfsd_attrs via the designated initializer, then immediately sets the source pointers to NULL. The subsequent conflict guard tests the already-nilled source fields, making it permanently dead code: if (create->cr_acl) { if (create->cr_dpacl || create->cr_pacl) /* always false */ When a client encodes both FATTR4_WORD0_ACL and FATTR4_WORD2_POSIX_{DEFAULT,ACCESS}_ACL in the same CREATE fattr bitmap, nfsd4_acl_to_attr() overwrites attrs.na_pacl/na_dpacl without releasing the originals, leaking two posix_acl slab objects per request. Repeated requests cause unbounded slab exhaustion. Fix by checking attrs.na_dpacl/na_pacl (the stolen values) instead of the nilled create->cr_dpacl/cr_pacl, matching the correct pattern already used in nfsd4_setattr().
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: d2ca50606f5f0235d7780c1cd73b6614a5d07620 , < 8371cc5c0a2cc2a71b3dcfd47ff1f7fcfc526a5e (git)
Affected: d2ca50606f5f0235d7780c1cd73b6614a5d07620 , < a60f25a800846ab8e5a13f8a9d05111f2aee55a7 (git)
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Linux Linux Affected: 7.0
Unaffected: 0 , < 7.0 (semver)
Unaffected: 7.1.3 , ≤ 7.1.* (semver)
Unaffected: 7.2-rc1 , ≤ * (original_commit_for_fix)
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        }
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/a60f25a800846ab8e5a13f8a9d05111f2aee55a7"
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    "datePublished": "2026-07-19T12:01:57.816Z",
    "dateReserved": "2026-06-09T07:44:35.402Z",
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    "state": "PUBLISHED"
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    "redhat_vex": {
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      "cve": "CVE-2026-53395",
      "id": "CVE-2026-53395",
      "initial_release_date": "2026-07-19T00:00:00+00:00",
      "product_status:known_affected": "90",
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: nfsd: fix dead ACL conflict guard in nfsd4_create",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53395.json",
      "version": "3"
    }
  }
}



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  • 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.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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