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CVE-2026-89673 (GCVE-0-2026-89673)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:45 – Updated: 2026-09-14 12:01
VLAI
Title
nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo nfsd4_ff_encode_getdeviceinfo() computes the da_addr_body reservation as 16 + netid_len + addr_len, but the subsequent xdr_encode_opaque() calls emit 8 + round_up(netid_len, 4) + round_up(addr_len, 4) bytes. The mismatch means the declared da_addr_body length exceeds the actual encoded data by 2-8 bytes on every flexfile GETDEVICEINFO reply, leaking stale reply-page content to the client and mis-aligning the subsequent version list decode. Use xdr_align_size() for each string length to match what xdr_encode_opaque() actually writes.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: efcae97fa425ca6db9d126e37daccf2d7225cb09 , < 88bce7e326c368d7df15126ccac537e54bebd467 (git)
Affected: efcae97fa425ca6db9d126e37daccf2d7225cb09 , < 74015b7be806ad9e21d46f7bd2831df280c6c783 (git)
Affected: efcae97fa425ca6db9d126e37daccf2d7225cb09 , < 41ebca28e17f84293650598f86bd69532ec1a8e0 (git)
Affected: efcae97fa425ca6db9d126e37daccf2d7225cb09 , < 62e5949f0dd5ec837af144860ff908369df4c7c9 (git)
Affected: efcae97fa425ca6db9d126e37daccf2d7225cb09 , < 8b989aaec85e1293a871d602590c951fe44b8647 (git)
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Linux Linux Affected: 6.4.16 , < 6.6.157 (semver)
Affected: 6.4.16 , < 6.12.109 (semver)
Affected: 6.4.16 , < 6.18.50 (semver)
Affected: 6.4.16 , < 7.2.4 (semver)
Affected: 6.4.16 , < 7.3-rc1 (semver)
guessed Create a notification for this product.
Show details on NVD website
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{
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix XDR padding calculation in ff_encode_getdeviceinfo\n\nnfsd4_ff_encode_getdeviceinfo() computes the da_addr_body reservation\nas 16 + netid_len + addr_len, but the subsequent xdr_encode_opaque()\ncalls emit 8 + round_up(netid_len, 4) + round_up(addr_len, 4) bytes.\nThe mismatch means the declared da_addr_body length exceeds the actual\nencoded data by 2-8 bytes on every flexfile GETDEVICEINFO reply,\nleaking stale reply-page content to the client and mis-aligning the\nsubsequent version list decode.\n\nUse xdr_align_size() for each string length to match what\nxdr_encode_opaque() actually writes."
        }
      ],
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    "cveId": "CVE-2026-89673",
    "datePublished": "2026-09-11T19:45:58.149Z",
    "dateReserved": "2026-09-11T19:38:34.746Z",
    "dateUpdated": "2026-09-14T12:01:58.863Z",
    "state": "PUBLISHED"
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      "current_release_date": "2026-09-15T05:08:11+00:00",
      "cve": "CVE-2026-89673",
      "id": "CVE-2026-89673",
      "initial_release_date": "2026-09-11T19:45:58.149000+00:00",
      "product_status:known_affected": "2",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux Kernel (nfsd): Information disclosure due to XDR padding calculation error",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89673.json",
      "version": "3"
    }
  }
}



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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

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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.