Vyper before 0.2.6 Call Stack Corruption via Complex Type Function Arguments

{
  "id": "09bb11c0f9b80f29bfedca252d53f58df2445bda02f95a44adf0f6cbda6d2ada",
  "url": "https://www.cve.org/CVERecord?id=CVE-2020-37287",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Vyper before 0.2.6 Call Stack Corruption via Complex Type Function Arguments",
    "summary": "Vyper before 0.2.6 contains a call stack corruption vulnerability that causes incorrect function outputs when complex types with non-base members are passed as arguments. Contracts passing multi-dimensional arrays or structs to internal or external functions receive corrupted values because the compiler assumed each subtype size is 32.",
    "evidence": "cve:CVE-2020-37287",
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            "version": "4.0",
            "Recovery": "NOT_DEFINED",
            "baseScore": 8.2,
            "Automatable": "NOT_DEFINED",
            "attackVector": "NETWORK",
            "baseSeverity": "HIGH",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
            "exploitMaturity": "NOT_DEFINED",
            "providerUrgency": "NOT_DEFINED",
            "userInteraction": "NONE",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "privilegesRequired": "NONE",
            "subIntegrityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH",
            "subAvailabilityImpact": "NONE",
            "vulnAvailabilityImpact": "NONE",
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            "availabilityImpact": "NONE",
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          }
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      "affected": [
        {
          "vendor": "vyperlang",
          "product": "vyper",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "0.2.6",
              "versionType": "python"
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              "status": "unaffected",
              "version": "0.2.6",
              "versionType": "python"
            }
          ],
          "packageURL": "pkg:pypi/vyper",
          "defaultStatus": "unaffected"
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      ],
      "modified": "2026-10-28T15:00:19.800Z",
      "provider": "cve",
      "references": [
        "https://github.com/vyperlang/vyper/security/advisories/GHSA-4v7v-gqf9-ww2g",
        "https://www.vulncheck.com/advisories/vyper-before-0.2.6-call-stack-corruption-via-complex-type-function-arguments"
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                    "id": "CVE-2020-37287",
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                        "Exploitation": "none"
                      },
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                        "Automatable": "no"
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                        "Technical Impact": "partial"
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                    "version": "2.0.3",
                    "timestamp": "2026-10-28T14:59:53.649860Z"
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  "source_id": "core-cve",
  "document_id": 454316,
  "published_at": "2026-10-21T00:36:16.257+00:00"
}