CVE-2026-53394

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: nfsd: avoid leaking pre-allocated openowner on unconfirmed retry race When find_or_alloc_open_stateowner() encounters an unconfirmed owner, it calls release_openowner() and sets oo = NULL. Control then falls through past the `if (oo)` guard -- which would have freed any pre-allocated `new` -- and unconditionally executes `new = alloc_stateowner(...)`. If `new` was already allocated on a prior iteration, the pointer is silently overwritten and the previous allocation (slab object + owner name buffer) is leaked. This requires a race: two NFSv4.0 OPEN threads with the same owner string, where a concurrent thread inserts a new unconfirmed owner into the hash between retry iterations. The window is narrow but repeatable under adversarial conditions. Fix by adding `goto retry` after `oo = NULL` so the already-allocated `new` is reused on the next iteration rather than overwritten.

Severity

HIGH

CVSS score

7.5 (v3.1)

Vulnerability status

Modified

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-07-19 12:16:50.480000

Last modified

2026-10-19 20:19:18.173000

View original CVE JSON

{
  "id": "CVE-2026-53394",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-19T12:16:50.480",
  "lastModified": "2026-10-19T20:19:18.173",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: avoid leaking pre-allocated openowner on unconfirmed retry race\n\nWhen find_or_alloc_open_stateowner() encounters an unconfirmed owner, it\ncalls release_openowner() and sets oo = NULL. Control then falls through\npast the `if (oo)` guard -- which would have freed any pre-allocated\n`new` -- and unconditionally executes `new = alloc_stateowner(...)`. If\n`new` was already allocated on a prior iteration, the pointer is\nsilently overwritten and the previous allocation (slab object + owner\nname buffer) is leaked.\n\nThis requires a race: two NFSv4.0 OPEN threads with the same owner\nstring, where a concurrent thread inserts a new unconfirmed owner into\nthe hash between retry iterations. The window is narrow but repeatable\nunder adversarial conditions.\n\nFix by adding `goto retry` after `oo = NULL` so the already-allocated\n`new` is reused on the next iteration rather than overwritten."
    }
  ],
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          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
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