Vulnerability from cleanstart
Published
2026-06-10 00:59
Modified
2026-06-09 07:15
Summary
When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash
Details

Multiple security vulnerabilities affect the kor package. When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash. See references for individual vulnerability details.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "kor"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.6.7-r0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [],
  "database_specific": {},
  "details": "Multiple security vulnerabilities affect the kor package. When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash. See references for individual vulnerability details.",
  "id": "CLEANSTART-2026-ZH72202",
  "modified": "2026-06-09T07:15:43Z",
  "published": "2026-06-10T00:59:24.602505Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/cleanstart-dev/cleanstart-security-advisories/tree/main/advisories/2026/CLEANSTART-2026-ZH72202.json"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-33811"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-33814"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-39820"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-39823"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-39825"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-39826"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-39836"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-42499"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33811"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33814"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39820"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39823"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39825"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39826"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39836"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42499"
    }
  ],
  "related": [],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash",
  "upstream": [
    "CVE-2026-33811",
    "CVE-2026-33814",
    "CVE-2026-39820",
    "CVE-2026-39823",
    "CVE-2026-39825",
    "CVE-2026-39826",
    "CVE-2026-39836",
    "CVE-2026-42499"
  ]
}



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