CVE-2026-47778

{
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          "role": "CISA Coordinator",
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              "automatable": "no"
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            {
              "technicalImpact": "partial"
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          "version": "2.0.3",
          "timestamp": "2026-06-27T02:52:00.418621Z"
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          "version": "3.1",
          "baseScore": 4.4,
          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "HIGH",
          "availabilityImpact": "NONE",
          "privilegesRequired": "HIGH",
          "confidentialityImpact": "HIGH"
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          "vendor": "envoyproxy",
          "product": "envoy",
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              "version": ">= 1.38.0, < 1.38.1"
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              "version": ">= 1.37.0, < 1.37.3"
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              "version": "< 1.35.11"
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  "published": "2026-06-26T18:16:59.480",
  "references": [
    {
      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-f8x4-rw5x-f3r7",
      "tags": [
        "Exploit",
        "Vendor Advisory",
        "Mitigation"
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    {
      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-f8x4-rw5x-f3r7",
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  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "type": "Secondary",
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      "description": [
        {
          "lang": "en",
          "value": "CWE-158"
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    {
      "lang": "en",
      "value": "Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, a structural flaw was identified in DefaultCertValidator::verifySubjectAltName where the extracted DNS SAN string is cast to a C-style string using .c_str() before being passed to the Utility::dnsNameMatch() algorithm. If the attacker serves a certificate with a dNSName SAN containing an embedded NUL byte, the helper Utility::generalNameAsString captures the complete string including the NUL. However, when .c_str() evaluates it, implicit conversion to absl::string_view inside dnsNameMatch relies on strlen(), prematurely truncating the evaluation context. Envoy evaluates trucated string against the exact required config_san match and returns true, thereby successfully validating the string with the Nul byte for an upstream routing. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1."
    }
  ],
  "lastModified": "2026-06-29T18:49:25.843",
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