← Back to CVE Explorer

CVE-2026-64392

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: use opener credentials for delete-on-close Delete-on-close can be completed by deferred or durable handle teardown, where no request work is available. Both the base-file unlink and the ADS xattr removal consequently run with the ksmbd worker credentials and can bypass filesystem permission checks. Run both operations with the credentials captured in struct file when the handle was opened. This preserves the authenticated user's fsuid, fsgid, supplementary groups and capability restrictions at final close.

Severity
CRITICAL
CVSS score
9.1 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-25 10:17:22.557000
Last modified
2026-10-30 13:19:36.017000
View original CVE JSON 
{
  "id": "CVE-2026-64392",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-25T10:17:22.557",
  "lastModified": "2026-10-30T13:19:36.017",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: use opener credentials for delete-on-close\n\nDelete-on-close can be completed by deferred or durable handle teardown,\nwhere no request work is available. Both the base-file unlink and the ADS\nxattr removal consequently run with the ksmbd worker credentials and can\nbypass filesystem permission checks.\n\nRun both operations with the credentials captured in struct file when the\nhandle was opened. This preserves the authenticated user's fsuid, fsgid,\nsupplementary groups and capability restrictions at final close."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/smb/server/vfs.c",
            "fs/smb/server/vfs_cache.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "f44158485826c076335d6860d35872271a83791d",
              "lessThan": "3cb2e6e2a6798909507b9d695e4b80e685e72d26",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f44158485826c076335d6860d35872271a83791d",
              "lessThan": "f08b3f451f12eee4abd8a5981803bc36db84458b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f44158485826c076335d6860d35872271a83791d",
              "lessThan": "18c59109bb6fb816d5102171666f87cf1e29901d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f44158485826c076335d6860d35872271a83791d",
              "lessThan": "e72c15085b6d86f45d224d98aa75b5cace4aaab9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f44158485826c076335d6860d35872271a83791d",
              "lessThan": "4b7059974549d278e30fe70e2a4e421f9839817d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f44158485826c076335d6860d35872271a83791d",
              "lessThan": "52e2f21911158ec961cd5aae19c56460db382af0",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/smb/server/vfs.c",
            "fs/smb/server/vfs_cache.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.15",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.15",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.145",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.96",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.39",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.4",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "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:H/A:H",
          "baseScore": 9.1,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.2
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "5.15",
              "versionEndExcluding": "6.6.145",
              "matchCriteriaId": "F27EDAAB-8124-4492-9129-5B21C14498D2"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.7",
              "versionEndExcluding": "6.12.96",
              "matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.13",
              "versionEndExcluding": "6.18.39",
              "matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.19",
              "versionEndExcluding": "7.1.4",
              "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/18c59109bb6fb816d5102171666f87cf1e29901d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/3cb2e6e2a6798909507b9d695e4b80e685e72d26",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4b7059974549d278e30fe70e2a4e421f9839817d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/52e2f21911158ec961cd5aae19c56460db382af0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/e72c15085b6d86f45d224d98aa75b5cace4aaab9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/f08b3f451f12eee4abd8a5981803bc36db84458b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    }
  ]
}