FKIE_CVE-2026-47775

Vulnerability from fkie_nvd - Published: 2026-06-26 18:16 - Updated: 2026-06-29 18:10
Severity
6.8 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Summary
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.
References
security-advisories@github.comhttps://github.com/envoyproxy/envoy/security/advisories/GHSA-396h-jpq4-vc7pExploit, Vendor Advisory, Mitigation
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/envoyproxy/envoy/security/advisories/GHSA-396h-jpq4-vc7pExploit, Vendor Advisory, Mitigation
Impacted products
Vendor Product Version
envoyproxy envoy *
envoyproxy envoy *
envoyproxy envoy *
envoyproxy envoy *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "envoy",
          "vendor": "envoyproxy",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 1.38.0, \u003c 1.38.1"
            },
            {
              "status": "affected",
              "version": "\u003e= 1.37.0, \u003c 1.37.3"
            },
            {
              "status": "affected",
              "version": "\u003e= 1.36.0, \u003c 1.36.7"
            },
            {
              "status": "affected",
              "version": "\u003c 1.35.11"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D0D8A448-3D11-4236-A3E1-BEF6537F7B78",
              "versionEndExcluding": "1.35.11",
              "versionStartIncluding": "1.35.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "C0A19272-7178-4FCE-A4D3-5E578A871D4D",
              "versionEndExcluding": "1.36.7",
              "versionStartIncluding": "1.36.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "24F12FF2-A40F-4C2C-B9C4-F59A22B99843",
              "versionEndExcluding": "1.37.3",
              "versionStartIncluding": "1.37.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "54B4E89D-3622-4F96-A599-E85109E8D4DD",
              "versionEndExcluding": "1.38.1",
              "versionStartIncluding": "1.38.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "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\u0027s 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\u0027s access token. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1."
    }
  ],
  "id": "CVE-2026-47775",
  "lastModified": "2026-06-29T18:10:33.463",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.2,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-47775",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-29T15:05:22.645121Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-26T18:16:59.350",
  "references": [
    {
      "source": "security-advisories@github.com",
      "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"
      ],
      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-396h-jpq4-vc7p"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-209"
        },
        {
          "lang": "en",
          "value": "CWE-327"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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