FKIE_CVE-2026-39822

Vulnerability from fkie_nvd - Published: 2026-07-08 17:17 - Updated: 2026-07-08 20:16
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbolic link and the path ends in /. For example, 'root.Open("symlink/")' will open "symlink" even when "symlink" is a symbolic link pointing outside of the root.
References
security@golang.orghttps://go.dev/cl/797880
security@golang.orghttps://go.dev/issue/79005
security@golang.orghttps://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc
security@golang.orghttps://pkg.go.dev/vuln/GO-2026-4970
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "os",
          "product": "os",
          "programRoutines": [
            {
              "name": "rootOpenFileNolog"
            },
            {
              "name": "openRootInRoot"
            },
            {
              "name": "OpenInRoot"
            },
            {
              "name": "Root.Create"
            },
            {
              "name": "Root.Open"
            },
            {
              "name": "Root.OpenFile"
            },
            {
              "name": "Root.OpenRoot"
            },
            {
              "name": "Root.ReadFile"
            },
            {
              "name": "Root.WriteFile"
            },
            {
              "name": "rootFS.Open"
            },
            {
              "name": "rootFS.ReadDir"
            },
            {
              "name": "rootFS.ReadFile"
            }
          ],
          "vendor": "Go standard library",
          "versions": [
            {
              "lessThan": "1.25.12",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.26.5",
              "status": "affected",
              "version": "1.26.0-0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.27.0-rc.2",
              "status": "affected",
              "version": "1.27.0-0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "security@golang.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbolic link and the path ends in /. For example, \u0027root.Open(\"symlink/\")\u0027 will open \"symlink\" even when \"symlink\" is a symbolic link pointing outside of the root."
    }
  ],
  "id": "CVE-2026-39822",
  "lastModified": "2026-07-08T20:16:49.060",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-39822",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-08T18:06:16.360721Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-08T17:17:21.310",
  "references": [
    {
      "source": "security@golang.org",
      "url": "https://go.dev/cl/797880"
    },
    {
      "source": "security@golang.org",
      "url": "https://go.dev/issue/79005"
    },
    {
      "source": "security@golang.org",
      "url": "https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc"
    },
    {
      "source": "security@golang.org",
      "url": "https://pkg.go.dev/vuln/GO-2026-4970"
    }
  ],
  "sourceIdentifier": "security@golang.org",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-61"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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