CVE-2026-47775

{
  "id": "CVE-2026-47775",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-26T18:16:59.350",
  "lastModified": "2026-10-25T17:10:00.197",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "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, the OAuth2 HTTP filter's encrypt()/decrypt() functions use AES-256-CBC without an authentication tag (no HMAC, no AEAD). The /callback endpoint returns HTTP 302 on successful decryption and HTTP 401 on padding failure, creating a padding oracle. An attacker who obtains the encrypted CodeVerifier cookie can recover the plaintext PKCE code_verifier in ~6,200 requests (~100 seconds), then exchange it with a stolen authorization code to obtain the victim's access token. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1."
    },
    {
      "lang": "es",
      "value": "Envoy es un proxy de borde y de servicio de código abierto diseñado para aplicaciones nativas de la nube. Antes de 1.35.11, 1.36.7, 1.37.3 y 1.38.1, las funciones encrypt()/decrypt() del filtro HTTP de OAuth2 utilizan AES-256-CBC sin una etiqueta de autenticación (sin HMAC, sin AEAD). El endpoint /callback devuelve HTTP 302 en caso de descifrado exitoso y HTTP 401 en caso de fallo de relleno, creando un oráculo de relleno. Un atacante que obtiene la cookie CodeVerifier cifrada puede recuperar el code_verifier PKCE en texto plano en ~6.200 solicitudes (~100 segundos), luego intercambiarlo con un código de autorización robado para obtener el token de acceso de la víctima. Esta vulnerabilidad está corregida en 1.35.11, 1.36.7, 1.37.3 y 1.38.1."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "envoyproxy",
          "product": "envoy",
          "versions": [
            {
              "version": ">= 1.38.0, < 1.38.1",
              "status": "affected"
            },
            {
              "version": ">= 1.37.0, < 1.37.3",
              "status": "affected"
            },
            {
              "version": ">= 1.36.0, < 1.36.7",
              "status": "affected"
            },
            {
              "version": "< 1.35.11",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-29T15:05:22.645121Z",
          "id": "CVE-2026-47775",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-209"
        },
        {
          "lang": "en",
          "value": "CWE-327"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "1.35.0",
              "versionEndExcluding": "1.35.11",
              "matchCriteriaId": "D0D8A448-3D11-4236-A3E1-BEF6537F7B78"
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              "versionStartIncluding": "1.36.0",
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              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "1.37.0",
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              "matchCriteriaId": "24F12FF2-A40F-4C2C-B9C4-F59A22B99843"
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              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "1.38.0",
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  "references": [
    {
      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-396h-jpq4-vc7p",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Vendor Advisory",
        "Mitigation"
      ]
    },
    {
      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-396h-jpq4-vc7p",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory",
        "Mitigation"
      ]
    }
  ]
}