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CVE-2026-89636

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: clear ce->tgthint in free_tgts() When free_tgts() frees all structures in ce->tlist, ce->tgthint is left pointing to one of the freed cache_dfs_tgt structures. If ce->tgthint is not reset before it is used later, it results in a use-after-free. Set ce->tgthint to NULL in free_tgts() after the elements are freed to reflect that no elements remain.

Severity
CRITICAL
CVSS score
9.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-11 20:19:49.243000
Last modified
2026-10-19 09:18:00.640000
View original CVE JSON
{
  "id": "CVE-2026-89636",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:49.243",
  "lastModified": "2026-10-19T09:18:00.640",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: clear ce->tgthint in free_tgts()\n\nWhen free_tgts() frees all structures in ce->tlist, ce->tgthint\nis left pointing to one of the freed cache_dfs_tgt structures.\n\nIf ce->tgthint is not reset before it is used later, it results\nin a use-after-free.\n\nSet ce->tgthint to NULL in free_tgts() after the elements are\nfreed to reflect that no elements remain."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/smb/client/dfs_cache.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "54be1f6c1c37498bba557049df646cc239fa37e3",
              "lessThan": "14f60e959b5ac813715ff72e127beb3584ddabf6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "54be1f6c1c37498bba557049df646cc239fa37e3",
              "lessThan": "3ff9462bb7a06d8d32a1dc02d39580b078ec9e55",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "54be1f6c1c37498bba557049df646cc239fa37e3",
              "lessThan": "7507bd1885643d0461a6017767492450af1ce2a3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "54be1f6c1c37498bba557049df646cc239fa37e3",
              "lessThan": "9ab46a13798a61d9d020b01d4e57efdabe6624fa",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "54be1f6c1c37498bba557049df646cc239fa37e3",
              "lessThan": "5baab40404a9393bcc0b7b8f1950bf2c307e0984",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "54be1f6c1c37498bba557049df646cc239fa37e3",
              "lessThan": "b1b741cf8e7ce1b91d937e23decd3d3358748700",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/smb/client/dfs_cache.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.0",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.0",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.109",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.50",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "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:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T19:24:47.621556Z",
          "id": "CVE-2026-89636",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/14f60e959b5ac813715ff72e127beb3584ddabf6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3ff9462bb7a06d8d32a1dc02d39580b078ec9e55",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5baab40404a9393bcc0b7b8f1950bf2c307e0984",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7507bd1885643d0461a6017767492450af1ce2a3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9ab46a13798a61d9d020b01d4e57efdabe6624fa",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b1b741cf8e7ce1b91d937e23decd3d3358748700",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}