GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2023-53680 (GCVE-0-2023-53680)

Vulnerability from cvelistv5 – Published: 2025-10-07 15:21 – Updated: 2026-08-05 09:15
VLAI
Title
NFSD: Avoid calling OPDESC() with ops->opnum == OP_ILLEGAL
Summary
In the Linux kernel, the following vulnerability has been resolved: NFSD: Avoid calling OPDESC() with ops->opnum == OP_ILLEGAL OPDESC() simply indexes into nfsd4_ops[] by the op's operation number, without range checking that value. It assumes callers are careful to avoid calling it with an out-of-bounds opnum value. nfsd4_decode_compound() is not so careful, and can invoke OPDESC() with opnum set to OP_ILLEGAL, which is 10044 -- well beyond the end of nfsd4_ops[].
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 CPE status
Linux Linux Affected: f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8 , < 50827896c365e0f6c8b55ed56d444dafd87c92c5 (git)
Affected: f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8 , < a64160124d5a078be0c380b1e8a0bad2d040d3a1 (git)
Affected: f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8 , < ffcbcf087581ae68ddc0a21460f7ecd4315bdd0e (git)
Affected: f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8 , < f352c41fa718482979e7e6b71b4da2b718e381cc (git)
Affected: f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8 , < 804d8e0a6e54427268790472781e03bc243f4ee3 (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.14
Unaffected: 0 , < 4.14 (semver)
Unaffected: 5.10.220 , ≤ 5.10.* (semver)
Unaffected: 5.15.107 , ≤ 5.15.* (semver)
Unaffected: 6.1.24 , ≤ 6.1.* (semver)
Unaffected: 6.2.11 , ≤ 6.2.* (semver)
Unaffected: 6.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4xdr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "50827896c365e0f6c8b55ed56d444dafd87c92c5",
              "status": "affected",
              "version": "f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8",
              "versionType": "git"
            },
            {
              "lessThan": "a64160124d5a078be0c380b1e8a0bad2d040d3a1",
              "status": "affected",
              "version": "f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8",
              "versionType": "git"
            },
            {
              "lessThan": "ffcbcf087581ae68ddc0a21460f7ecd4315bdd0e",
              "status": "affected",
              "version": "f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8",
              "versionType": "git"
            },
            {
              "lessThan": "f352c41fa718482979e7e6b71b4da2b718e381cc",
              "status": "affected",
              "version": "f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8",
              "versionType": "git"
            },
            {
              "lessThan": "804d8e0a6e54427268790472781e03bc243f4ee3",
              "status": "affected",
              "version": "f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4xdr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.14"
            },
            {
              "lessThan": "4.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.220",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.107",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.24",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.2.*",
              "status": "unaffected",
              "version": "6.2.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.220",
                  "versionStartIncluding": "4.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.107",
                  "versionStartIncluding": "4.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.24",
                  "versionStartIncluding": "4.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.2.11",
                  "versionStartIncluding": "4.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.3",
                  "versionStartIncluding": "4.14",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Avoid calling OPDESC() with ops-\u003eopnum == OP_ILLEGAL\n\nOPDESC() simply indexes into nfsd4_ops[] by the op\u0027s operation\nnumber, without range checking that value. It assumes callers are\ncareful to avoid calling it with an out-of-bounds opnum value.\n\nnfsd4_decode_compound() is not so careful, and can invoke OPDESC()\nwith opnum set to OP_ILLEGAL, which is 10044 -- well beyond the end\nof nfsd4_ops[]."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The defect is in nfsd\u0027s NFSv4 COMPOUND XDR decoder, driven directly by bytes a remote client sends to TCP/2049. Any host able to reach the NFS server can supply the malformed opnum.\nAC:L - Triggering requires only a single COMPOUND request carrying an opnum outside the legal range for the minorversion (e.g. 0, 1, 2, or anything above LAST_NFS42_OP); it is deterministic with no race, timing, or memory-layout dependency.\nPR:N - nfsd4_decode_compound() runs during RPC argument decode, before any export permission, filehandle, or NFSv4 state/authorization check in nfsd4_proc_compound(); with the default AUTH_SYS flavor no principal is authenticated, so an unauthenticated network peer reaches this code.\nUI:N - The attacker sends the malformed COMPOUND unilaterally; nothing is required of any local user or administrator on the server.\nS:U - The out-of-bounds pointer and any resulting fault stay within the kernel\u0027s own security authority on the NFS server, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:N - Nothing read from the out-of-bounds address is ever encoded into the NFS reply \u2014 the descriptor fields are only tested as flags or used as a call target \u2014 and the offset is a hardcoded constant the attacker cannot steer, so no information is disclosed to the attacker.\nI:N - The bug only forms and stores an out-of-bounds read pointer; no attacker-controlled data is written anywhere and no kernel memory is modified.\nA:H - The wild pointer points roughly 550 KB past a const array in nfsd\u0027s module mapping, and any dereference of it (e.g. the indirect call OPDESC(op)-\u003eop_rsize_bop() in nfsd4_max_reply(), which is protected only by an easily-missed open-coded OP_ILLEGAL check) faults in an nfsd kthread and takes the NFS service down. A remote unauthenticated attacker can repeat the request at will, so the availability impact is scored High."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:15:31.911Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/50827896c365e0f6c8b55ed56d444dafd87c92c5"
        },
        {
          "url": "https://git.kernel.org/stable/c/a64160124d5a078be0c380b1e8a0bad2d040d3a1"
        },
        {
          "url": "https://git.kernel.org/stable/c/ffcbcf087581ae68ddc0a21460f7ecd4315bdd0e"
        },
        {
          "url": "https://git.kernel.org/stable/c/f352c41fa718482979e7e6b71b4da2b718e381cc"
        },
        {
          "url": "https://git.kernel.org/stable/c/804d8e0a6e54427268790472781e03bc243f4ee3"
        }
      ],
      "title": "NFSD: Avoid calling OPDESC() with ops-\u003eopnum == OP_ILLEGAL",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2023-53680",
    "datePublished": "2025-10-07T15:21:34.626Z",
    "dateReserved": "2025-10-07T15:16:59.664Z",
    "dateUpdated": "2026-08-05T09:15:31.911Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2023-53680",
      "date": "2026-09-17",
      "epss": "0.00298",
      "percentile": "0.22582"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2023-53680\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-10-07T16:15:52.160\",\"lastModified\":\"2026-08-04T10:19:17.847\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nNFSD: Avoid calling OPDESC() with ops-\u003eopnum == OP_ILLEGAL\\n\\nOPDESC() simply indexes into nfsd4_ops[] by the op\u0027s operation\\nnumber, without range checking that value. It assumes callers are\\ncareful to avoid calling it with an out-of-bounds opnum value.\\n\\nnfsd4_decode_compound() is not so careful, and can invoke OPDESC()\\nwith opnum set to OP_ILLEGAL, which is 10044 -- well beyond the end\\nof nfsd4_ops[].\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/nfsd/nfs4xdr.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8\",\"lessThan\":\"50827896c365e0f6c8b55ed56d444dafd87c92c5\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8\",\"lessThan\":\"a64160124d5a078be0c380b1e8a0bad2d040d3a1\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8\",\"lessThan\":\"ffcbcf087581ae68ddc0a21460f7ecd4315bdd0e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8\",\"lessThan\":\"f352c41fa718482979e7e6b71b4da2b718e381cc\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8\",\"lessThan\":\"804d8e0a6e54427268790472781e03bc243f4ee3\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/nfsd/nfs4xdr.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"4.14\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"4.14\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.220\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.107\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.24\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.2.11\",\"lessThanOrEqual\":\"6.2.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.3\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-787\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.14\",\"versionEndExcluding\":\"5.10.220\",\"matchCriteriaId\":\"DE4ACFB8-0C5D-4961-BEB5-F3178AF7C9FB\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.11\",\"versionEndExcluding\":\"5.15.107\",\"matchCriteriaId\":\"6BCC0C73-754E-4985-A087-F74888650709\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.24\",\"matchCriteriaId\":\"E6EC432F-985F-450F-954E-7EAD42ADA1F8\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.2.11\",\"matchCriteriaId\":\"93C03C9A-798F-4CD5-912F-A436BFA0CC7E\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.3:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"B8E3B0E8-FA27-4305-87BB-AF6C25B160CB\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.3:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"A47F0FC3-CE52-4BA1-BA51-22F783938431\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.3:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"3583026A-27EC-4A4C-850A-83F2AF970673\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.3:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"DC271202-7570-4505-89A4-D602D47BFD00\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.3:rc5:*:*:*:*:*:*\",\"matchCriteriaId\":\"D413BB6D-4F74-4C7D-9163-47786619EF53\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/50827896c365e0f6c8b55ed56d444dafd87c92c5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/804d8e0a6e54427268790472781e03bc243f4ee3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/a64160124d5a078be0c380b1e8a0bad2d040d3a1\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/f352c41fa718482979e7e6b71b4da2b718e381cc\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/ffcbcf087581ae68ddc0a21460f7ecd4315bdd0e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-04T19:16:39+00:00",
      "cve": "CVE-2023-53680",
      "id": "CVE-2023-53680",
      "initial_release_date": "2023-01-01T00:00:00+00:00",
      "product_status:fixed": "630",
      "product_status:known_affected": "170",
      "product_status:known_not_affected": "132",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: NFSD: Avoid calling OPDESC() with ops-\u003eopnum == OP_ILLEGAL",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-53680.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.