CVE-2025-21795 (GCVE-0-2025-21795)

Vulnerability from cvelistv5 – Published: 2025-02-27 02:18 – Updated: 2026-10-15 01:04
VLAI
Title
NFSD: fix hang in nfsd4_shutdown_callback
Summary
In the Linux kernel, the following vulnerability has been resolved: NFSD: fix hang in nfsd4_shutdown_callback If nfs4_client is in courtesy state then there is no point to send the callback. This causes nfsd4_shutdown_callback to hang since cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP notifies NFSD that the connection was dropped. This patch modifies nfsd4_run_cb_work to skip the RPC call if nfs4_client is in courtesy state.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7033 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 67ef9e5fd737eab2495f2586df7e9ea30caa1b77 , < abed68027ea3ab893ac85cc46a00e2e64a324239 (git)
Affected: 26540b8940a2e21582afa61a6fb8af87310bac72 , < efa8a261c575f816c7e79a87aeb3ef8a0bd6b221 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < 38d345f612503b850c2973e5a879f88e441b34d7 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < 23ad7797c74cd8f7f90617f1e59a8703e2b43908 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < cedfbb92cf97a6bff3d25633001d9c44442ee854 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < e88d2451cd42e025465d6b51fd716a47b0b3800d (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < 036ac2778f7b28885814c6fbc07e156ad1624d03 (git)
Affected: 5.10.220 , < 5.10.235 (semver)
Affected: 5.15.154 , < 5.15.179 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 5.19
Unaffected: 0 , < 5.19 (semver)
Unaffected: 5.10.235 , ≤ 5.10.* (semver)
Unaffected: 5.15.179 , ≤ 5.15.* (semver)
Unaffected: 6.1.129 , ≤ 6.1.* (semver)
Unaffected: 6.6.79 , ≤ 6.6.* (semver)
Unaffected: 6.12.16 , ≤ 6.12.* (semver)
Unaffected: 6.13.4 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP Affected: V3.1.5 , < * (custom)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP Affected: V3.1.6 , < * (custom)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP Affected: V3.1.7 , < * (custom)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP Affected: V3.1.5 , < * (custom)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP Affected: V3.1.6 , < * (custom)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP Affected: V3.1.7 , < * (custom)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem Affected: 0 , < * (custom)
guessed Create a notification for this product.
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP Affected: V3.1.5 , < * (custom)
guessed Create a notification for this product.
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP Affected: V3.1.6 , < * (custom)
guessed Create a notification for this product.
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP Affected: V3.1.7 , < * (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-03T20:59:38.867Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"
          },
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "affected": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.5",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.6",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.7",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.5",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.6",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.7",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.5",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.6",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.7",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.5",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.6",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.7",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.5",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.6",
                "versionType": "custom"
              }
            ]
          },
          {
            "defaultStatus": "unknown",
            "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.7",
                "versionType": "custom"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-15T01:04:27.946Z",
          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
        },
        "references": [
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
          },
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
          },
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
          },
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html"
          },
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-784472.html"
          }
        ],
        "x_adpType": "supplier"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4callback.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "abed68027ea3ab893ac85cc46a00e2e64a324239",
              "status": "affected",
              "version": "67ef9e5fd737eab2495f2586df7e9ea30caa1b77",
              "versionType": "git"
            },
            {
              "lessThan": "efa8a261c575f816c7e79a87aeb3ef8a0bd6b221",
              "status": "affected",
              "version": "26540b8940a2e21582afa61a6fb8af87310bac72",
              "versionType": "git"
            },
            {
              "lessThan": "38d345f612503b850c2973e5a879f88e441b34d7",
              "status": "affected",
              "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
              "versionType": "git"
            },
            {
              "lessThan": "23ad7797c74cd8f7f90617f1e59a8703e2b43908",
              "status": "affected",
              "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
              "versionType": "git"
            },
            {
              "lessThan": "cedfbb92cf97a6bff3d25633001d9c44442ee854",
              "status": "affected",
              "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
              "versionType": "git"
            },
            {
              "lessThan": "e88d2451cd42e025465d6b51fd716a47b0b3800d",
              "status": "affected",
              "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
              "versionType": "git"
            },
            {
              "lessThan": "036ac2778f7b28885814c6fbc07e156ad1624d03",
              "status": "affected",
              "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
              "versionType": "git"
            },
            {
              "lessThan": "5.10.235",
              "status": "affected",
              "version": "5.10.220",
              "versionType": "semver"
            },
            {
              "lessThan": "5.15.179",
              "status": "affected",
              "version": "5.15.154",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4callback.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.19"
            },
            {
              "lessThan": "5.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.235",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.179",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.129",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.79",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.13.*",
              "status": "unaffected",
              "version": "6.13.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.235",
                  "versionStartIncluding": "5.10.220",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.179",
                  "versionStartIncluding": "5.15.154",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.129",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.79",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.16",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.13.4",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.14",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: fix hang in nfsd4_shutdown_callback\n\nIf nfs4_client is in courtesy state then there is no point to send\nthe callback. This causes nfsd4_shutdown_callback to hang since\ncl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP\nnotifies NFSD that the connection was dropped.\n\nThis patch modifies nfsd4_run_cb_work to skip the RPC call if\nnfs4_client is in courtesy state."
        }
      ],
      "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 vulnerable code is in the in-kernel NFS server (nfsd) and is reached entirely through NFSv4 protocol operations (OPEN/delegation, LOCK) from a remote network client over the wire.\nAC:L - The attacker controls both sides \u2014 obtaining a delegation then dropping its connection to become a courtesy client, and issuing the conflicting operation that forces the recall \u2014 and the recall itself deterministically triggers the expiry that hangs on the in-flight SOFTCONN RPC, so the ~15-minute hang is reliably reproducible.\nPR:N - NFS exports commonly use AUTH_SYS (no real authentication) and may be accessible to a subnet or anonymously, so an unauthenticated network client can perform the OPEN/delegation and conflicting-lock operations needed; no verified privilege is required.\nUI:N - The attacker\u0027s own NFS operations set up and trigger the hang; no action by any legitimate user or administrator is needed.\nS:U - The hang is confined to the NFS server\u0027s own kernel context and workqueues; it does not cross a security/authority boundary such as a VM or IOMMU boundary.\nC:N - The defect is a wait/hang on an in-flight callback with no memory disclosure or out-of-bounds read; no confidential information is exposed.\nI:N - No data is modified or corrupted; the bug only stalls the callback-shutdown path and involves no write primitive or state alteration.\nA:H - `nfsd4_shutdown_callback` hangs for ~15 minutes, blocking the laundromat workqueue (all lease/state/delegation/lock cleanup) and lock-conflict resolution that flushes the same queue, and the stall can be triggered repeatedly \u2014 a severe denial of service of the NFS server."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:54:30.327Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/abed68027ea3ab893ac85cc46a00e2e64a324239"
        },
        {
          "url": "https://git.kernel.org/stable/c/efa8a261c575f816c7e79a87aeb3ef8a0bd6b221"
        },
        {
          "url": "https://git.kernel.org/stable/c/38d345f612503b850c2973e5a879f88e441b34d7"
        },
        {
          "url": "https://git.kernel.org/stable/c/23ad7797c74cd8f7f90617f1e59a8703e2b43908"
        },
        {
          "url": "https://git.kernel.org/stable/c/cedfbb92cf97a6bff3d25633001d9c44442ee854"
        },
        {
          "url": "https://git.kernel.org/stable/c/e88d2451cd42e025465d6b51fd716a47b0b3800d"
        },
        {
          "url": "https://git.kernel.org/stable/c/036ac2778f7b28885814c6fbc07e156ad1624d03"
        }
      ],
      "title": "NFSD: fix hang in nfsd4_shutdown_callback",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21795",
    "datePublished": "2025-02-27T02:18:31.538Z",
    "dateReserved": "2024-12-29T08:45:45.767Z",
    "dateUpdated": "2026-10-15T01:04:27.946Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-21795",
      "date": "2026-10-31",
      "epss": "0.00668",
      "percentile": "0.51929"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "fs/nfsd/nfs4callback.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "abed68027ea3ab893ac85cc46a00e2e64a324239",
                    "status": "affected",
                    "version": "67ef9e5fd737eab2495f2586df7e9ea30caa1b77",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "efa8a261c575f816c7e79a87aeb3ef8a0bd6b221",
                    "status": "affected",
                    "version": "26540b8940a2e21582afa61a6fb8af87310bac72",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "38d345f612503b850c2973e5a879f88e441b34d7",
                    "status": "affected",
                    "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "23ad7797c74cd8f7f90617f1e59a8703e2b43908",
                    "status": "affected",
                    "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "cedfbb92cf97a6bff3d25633001d9c44442ee854",
                    "status": "affected",
                    "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "e88d2451cd42e025465d6b51fd716a47b0b3800d",
                    "status": "affected",
                    "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "036ac2778f7b28885814c6fbc07e156ad1624d03",
                    "status": "affected",
                    "version": "66af25799940b26efd41ea6e648f75c41a48a2c2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "5.10.235",
                    "status": "affected",
                    "version": "5.10.220",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "5.15.179",
                    "status": "affected",
                    "version": "5.15.154",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "fs/nfsd/nfs4callback.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "5.19"
                  },
                  {
                    "lessThan": "5.19",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.235",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.179",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.129",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.79",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.16",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.13.*",
                    "status": "unaffected",
                    "version": "6.13.4",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.14",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          },
          {
            "affectedData": [
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.5",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.6",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.7",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.5",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.6",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.7",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.5",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.6",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.7",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.5",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.6",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.7",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.5",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.6",
                    "versionType": "custom"
                  }
                ]
              },
              {
                "defaultStatus": "unknown",
                "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "*",
                    "status": "affected",
                    "version": "V3.1.7",
                    "versionType": "custom"
                  }
                ]
              }
            ],
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "D4BB38DD-63BF-4CE7-B8DF-F7C5D678CC41",
                    "versionEndExcluding": "5.10.235",
                    "versionStartIncluding": "5.10.220",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "90BD6495-A356-4D15-B705-7922FE2BBD66",
                    "versionEndExcluding": "5.15.179",
                    "versionStartIncluding": "5.15.154",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "EE25DF79-9FB2-4DE2-93D0-BF8587BF37CA",
                    "versionEndExcluding": "6.1.129",
                    "versionStartIncluding": "5.19",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "B16AADE5-B2FD-4C14-B4E4-85E8EDAFE775",
                    "versionEndExcluding": "6.6.79",
                    "versionStartIncluding": "6.2",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "13C8DB18-FC60-425F-84E5-3EDDEC61B2FC",
                    "versionEndExcluding": "6.12.16",
                    "versionStartIncluding": "6.7",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "2A2093ED-74A9-43F9-AC72-50030F374EA4",
                    "versionEndExcluding": "6.13.4",
                    "versionStartIncluding": "6.13",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "186716B6-2B66-4BD0-852E-D48E71C0C85F",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "0D3E781C-403A-498F-9DA9-ECEE50F41E75",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: fix hang in nfsd4_shutdown_callback\n\nIf nfs4_client is in courtesy state then there is no point to send\nthe callback. This causes nfsd4_shutdown_callback to hang since\ncl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP\nnotifies NFSD that the connection was dropped.\n\nThis patch modifies nfsd4_run_cb_work to skip the RPC call if\nnfs4_client is in courtesy state."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: NFSD: se corrige el bloqueo en nfsd4_shutdown_callback Si nfs4_client est\u00e1 en estado de cortes\u00eda, no tiene sentido enviar la devoluci\u00f3n de llamada. Esto hace que nfsd4_shutdown_callback se bloquee ya que cl_cb_inflight no es 0. Este bloqueo dura unos 15 minutos hasta que TCP notifica a NFSD que se interrumpi\u00f3 la conexi\u00f3n. Este parche modifica nfsd4_run_cb_work para omitir la llamada RPC si nfs4_client est\u00e1 en estado de cortes\u00eda."
          }
        ],
        "id": "CVE-2025-21795",
        "lastModified": "2026-10-15T02:17:36.090",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 7.5,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 3.6,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2025-02-27T03:15:20.390",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/036ac2778f7b28885814c6fbc07e156ad1624d03"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/23ad7797c74cd8f7f90617f1e59a8703e2b43908"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/38d345f612503b850c2973e5a879f88e441b34d7"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/abed68027ea3ab893ac85cc46a00e2e64a324239"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/cedfbb92cf97a6bff3d25633001d9c44442ee854"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/e88d2451cd42e025465d6b51fd716a47b0b3800d"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/efa8a261c575f816c7e79a87aeb3ef8a0bd6b221"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"
          },
          {
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
          },
          {
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
          },
          {
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
          },
          {
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html"
          },
          {
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-784472.html"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "NVD-CWE-noinfo"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-10-30T01:02:59+00:00",
      "cve": "CVE-2025-21795",
      "id": "CVE-2025-21795",
      "initial_release_date": "2025-02-27T00:00:00+00:00",
      "product_status:fixed": "917",
      "product_status:known_affected": "42",
      "product_status:known_not_affected": "48",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: NFSD: fix hang in nfsd4_shutdown_callback",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-21795.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-10-16T00:58:32Z",
      "cve": "CVE-2025-21795",
      "id": "CVE-2025-21795",
      "initial_release_date": "2025-02-28T02:20:32Z",
      "product_status:known_affected": "463",
      "product_status:known_not_affected": "355",
      "product_status:recommended": "472",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-21795",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/2025/cve-2025-21795.json",
      "version": "61"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Loading timeline…




    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.