{
  "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-2026-63892",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-63892",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-07-19T14:55:03.568Z",
    "updatedAt": "2026-07-19T14:55:03.568Z",
    "importedAt": "2026-10-24T01:58:20.586Z",
    "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": "thunderbolt: property: Reject dir_len < 4 to prevent size_t underflow",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: property: Reject dir_len < 4 to prevent size_t underflow\n\nOn the non-root path, __tb_property_parse_dir() takes dir_len from\nentry->length (u16 widened to size_t).  Two distinct OOB conditions\nfollow when entry->length < 4:\n\n1. The non-root path begins with kmemdup(&block[dir_offset],\n   sizeof(*dir->uuid), ...) which always reads 4 dwords from\n   dir_offset.  tb_property_entry_valid() only enforces\n   dir_offset + entry->length <= block_len, so a crafted entry\n   with dir_offset close to the end of the property block and\n   entry->length in 0..3 passes that gate but lets the UUID copy\n   run off the block (e.g. dir_offset = 497, dir_len = 3 in a\n   500-dword block reads block[497..501]).\n\n2. After the kmemdup, content_len = dir_len - 4 underflows size_t\n   to ~SIZE_MAX, nentries becomes SIZE_MAX / 4, and the entry\n   walk runs OOB on each iteration until an entry fails\n   validation or the kernel oopses on an unmapped page.\n\nReject dir_len < 4 on the non-root path *before* the UUID kmemdup,\nwhich closes both holes.\n\nAlso move INIT_LIST_HEAD(&dir->properties) up to immediately after\nthe dir allocation so the new error-return path (and the existing\nuuid-alloc failure path) calling tb_property_free_dir() sees a\nwalkable list rather than the zero-initialized NULL next/prev that\nlist_for_each_entry_safe() would oops on.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "37abc4504fa19d8f9f1e87792e8a2b8fdb308e40"
            },
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "e2d4d51cf5785815fa4e91e0c019e3eb2506a84c"
            },
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "de618299190b418291609e6921557253bd417e25"
            },
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5506c825f14d810f0690b1f4367cb7249ebb387a"
            },
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "542a13890b742099c461d70920e97b14e568f6ec"
            },
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "d548179adcc87e1bc66b17e00352a1f536e76065"
            },
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3bec49ca55e08fb085cc4318f24b1b37eaab28cb"
            },
            {
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "status": "affected",
              "versionType": "git",
              "lessThan": "de21b59c29e31c5108ddc04210631bbfab81b997"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "4.15",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "4.15"
            },
            {
              "version": "5.10.259",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.210",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.176",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.143",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.93",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.35",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.0.12",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.0.*"
            },
            {
              "version": "7.1",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}