FKIE_CVE-2026-47736

Vulnerability from fkie_nvd - Published: 2026-07-14 20:17 - Updated: 2026-07-15 18:15
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, when PROXY protocol v1 support is enabled, Puma reads incoming bytes into an internal buffer while waiting for CRLF to determine whether a PROXY v1 line is present, allowing an attacker that continuously sends bytes without CRLF to cause unbounded in-process memory growth and additional CPU cost from repeatedly scanning the growing buffer. This issue is fixed in versions 7.2.1 and 8.0.2.
References
security-advisories@github.comhttps://github.com/puma/puma/commit/439c6136d9c2275721b7864db3ee78af7c80889f
security-advisories@github.comhttps://github.com/puma/puma/commit/ebe9db3929ab8299d19c8f5b41e8ef4f4b22fa58
security-advisories@github.comhttps://github.com/puma/puma/releases/tag/v7.2.1
security-advisories@github.comhttps://github.com/puma/puma/releases/tag/v8.0.2
security-advisories@github.comhttps://github.com/puma/puma/security/advisories/GHSA-qpgp-93vx-g8v8
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "puma",
          "vendor": "puma",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 5.5.0, \u003c 7.2.1"
            },
            {
              "status": "affected",
              "version": "\u003e= 8.0.0, \u003c 8.0.2"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, when PROXY protocol v1 support is enabled, Puma reads incoming bytes into an internal buffer while waiting for CRLF to determine whether a PROXY v1 line is present, allowing an attacker that continuously sends bytes without CRLF to cause unbounded in-process memory growth and additional CPU cost from repeatedly scanning the growing buffer. This issue is fixed in versions 7.2.1 and 8.0.2."
    }
  ],
  "id": "CVE-2026-47736",
  "lastModified": "2026-07-15T18:15:13.373",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-47736",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-15T14:27:41.068975Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-14T20:17:03.620",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/puma/puma/commit/439c6136d9c2275721b7864db3ee78af7c80889f"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/puma/puma/commit/ebe9db3929ab8299d19c8f5b41e8ef4f4b22fa58"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/puma/puma/releases/tag/v7.2.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/puma/puma/releases/tag/v8.0.2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/puma/puma/security/advisories/GHSA-qpgp-93vx-g8v8"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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