{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2025-21908",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-21908",
    "idYear": 2025,
    "status": "PUBLISHED",
    "publishedAt": "2025-04-01T15:40:48.171Z",
    "updatedAt": "2026-05-11T21:08:51.330Z",
    "importedAt": "2026-10-24T01:57:29.455Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFS: fix nfs_release_folio() to not deadlock via kcompactd writeback\n\nAdd PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so\nnfs_release_folio() can skip calling nfs_wb_folio() from kcompactd.\n\nOtherwise NFS can deadlock waiting for kcompactd enduced writeback which\nrecurses back to NFS (which triggers writeback to NFSD via NFS loopback\nmount on the same host, NFSD blocks waiting for XFS's call to\n__filemap_get_folio):\n\n6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds.\n\n{---\n[58] \"kcompactd0\"\n[<0>] folio_wait_bit+0xe8/0x200\n[<0>] folio_wait_writeback+0x2b/0x80\n[<0>] nfs_wb_folio+0x80/0x1b0 [nfs]\n[<0>] nfs_release_folio+0x68/0x130 [nfs]\n[<0>] split_huge_page_to_list_to_order+0x362/0x840\n[<0>] migrate_pages_batch+0x43d/0xb90\n[<0>] migrate_pages_sync+0x9a/0x240\n[<0>] migrate_pages+0x93c/0x9f0\n[<0>] compact_zone+0x8e2/0x1030\n[<0>] compact_node+0xdb/0x120\n[<0>] kcompactd+0x121/0x2e0\n[<0>] kthread+0xcf/0x100\n[<0>] ret_from_fork+0x31/0x40\n[<0>] ret_from_fork_asm+0x1a/0x30\n---}\n\n[akpm@linux-foundation.org: fix build]",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "96780ca55e3cbf4f150fd5a833a61492c9947b5b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ab0727d6e2196682351c25c1dd112136f6991f11"
            },
            {
              "version": "96780ca55e3cbf4f150fd5a833a61492c9947b5b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5ae31c54cff745832b9bd5b32e71f3d1b607cd1e"
            },
            {
              "version": "96780ca55e3cbf4f150fd5a833a61492c9947b5b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8253ff29edcb429a9a6c75710941c6a16a9a34b1"
            },
            {
              "version": "96780ca55e3cbf4f150fd5a833a61492c9947b5b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ce6d9c1c2b5cc785016faa11b48b6cd317eb367e"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.3",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.3"
            },
            {
              "version": "6.6.83",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.19",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.13.7",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.13.*"
            },
            {
              "version": "6.14",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}