CVE-2026-56857 (GCVE-0-2026-56857)
Vulnerability from cvelistv5
Published
2026-10-08 22:53
Modified
2026-10-09 15:36
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
Summary
On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction target even when that target is located outside the root. This only applies to operations where the last path component is a junction (path/to/junction, but not path/junction/target).
References
Impacted products
Vendor Product Version
Go standard library os Version: 0   ≤
Version: 1.27.0-0   ≤
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              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
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                "version": "2.0.3"
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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        }
      ],
      "problemTypes": [
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        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6604"
        }
      ],
      "title": "Root.Mkdir(All) can follow junctions out of the root on Windows in os"
    }
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}


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