{
  "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-2026-64294",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-64294",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-07-25T08:49:32.570Z",
    "updatedAt": "2026-08-23T12:45:40.258Z",
    "importedAt": "2026-10-24T01:58:25.636Z",
    "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": "mm: do file ownership checks with the proper mount idmap",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: do file ownership checks with the proper mount idmap\n\nEver since idmapped mounts were introduced, inode ownership checks (for\nside-channel protection) in mincore() and madvise(MADV_PAGEOUT) were done\nagainst the nop_mnt_idmap, which completely ignores the file's mount's\nidmap.  This results in odd edgecases like:\n\n1) mount/bind-mount with an idmap userA:userB:1\n2) userB runs an owner_or_capable() check on file that is owned by userA\non-disk/in-memory, but owned by userB after idmap translation\n3) owner_or_capable() mysteriously fails as the correct idmap wasn't supplied\n\nIn the case of mincore/madvise MADV_PAGEOUT, this is usually benign,\nbecause file_permission(file, MAY_WRITE) will probably succeed, as it uses\nthe proper idmap internally, but it does not need to be the case on e.g a\n0444 file where even the owner itself doesn't have permissions to write to\nit.\n\nSince this is clearly not trivial to get right, introduce a\nfile_owner_or_capable() that can carry the correct semantics, and switch\nthe various users in mm to it.\n\nThe issue was found by manual code inspection & an off-list discussion\nwith Jan Kara.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "9caccd41541a6f7d6279928d9f971f6642c361af",
              "status": "affected",
              "versionType": "git",
              "lessThan": "7368bec565bac3e536cd43579dbde1e715e6ba61"
            },
            {
              "version": "9caccd41541a6f7d6279928d9f971f6642c361af",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b2f3d94ea310bea9d36d53e9d9b3f45e86c1d893"
            },
            {
              "version": "9caccd41541a6f7d6279928d9f971f6642c361af",
              "status": "affected",
              "versionType": "git",
              "lessThan": "744b23aa430d52f5c8e4dbff7d71496d6643bed2"
            },
            {
              "version": "9caccd41541a6f7d6279928d9f971f6642c361af",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8344bdf0629457e532797b42d9d2bbf2a2900bbf"
            },
            {
              "version": "9caccd41541a6f7d6279928d9f971f6642c361af",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5c942ad7df75925ee166e7f0fb36892d8dde376b"
            },
            {
              "version": "9caccd41541a6f7d6279928d9f971f6642c361af",
              "status": "affected",
              "versionType": "git",
              "lessThan": "04ba248d02d9eaa3d9077b00a6134caa75fa3e90"
            },
            {
              "version": "9caccd41541a6f7d6279928d9f971f6642c361af",
              "status": "affected",
              "versionType": "git",
              "lessThan": "e187bc02f8fa4226d62814592cf064ee4557c470"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.12",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.12"
            },
            {
              "version": "5.15.217",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.184",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.145",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.96",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.39",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.1.4",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "version": "7.2",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}