ghsa-qpgp-93vx-g8v8

{
  "affected": [
    {
      "database_specific": {
        "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-qpgp-93vx-g8v8/GHSA-qpgp-93vx-g8v8.json"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "puma",
        "purl": "pkg:gem/puma"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0"
            },
            {
              "fixed": "8.0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "8.0.0",
        "8.0.1"
      ]
    },
    {
      "database_specific": {
        "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-qpgp-93vx-g8v8/GHSA-qpgp-93vx-g8v8.json"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "puma",
        "purl": "pkg:gem/puma"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.5.0"
            },
            {
              "fixed": "7.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.5.0",
        "5.5.1",
        "5.5.2",
        "5.6.0",
        "5.6.1",
        "5.6.2",
        "5.6.4",
        "5.6.5",
        "5.6.6",
        "5.6.7",
        "5.6.8",
        "5.6.9",
        "6.0.0",
        "6.0.1",
        "6.0.2",
        "6.1.0",
        "6.1.1",
        "6.2.0",
        "6.2.1",
        "6.2.2",
        "6.3.0",
        "6.3.1",
        "6.4.0",
        "6.4.1",
        "6.4.2",
        "6.4.3",
        "6.5.0",
        "6.6.0",
        "6.6.1",
        "7.0.0",
        "7.0.0.pre1",
        "7.0.1",
        "7.0.2",
        "7.0.3",
        "7.0.4",
        "7.1.0",
        "7.2.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-47736"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-08T23:55:44Z",
    "nvd_published_at": "2026-07-14T20:17:03Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\n[PROXY protocol support for Puma](https://github.com/puma/puma/issues/2651) was added in version 5.5.0.\n\nWhen PROXY protocol v1 support is enabled, Puma reads incoming bytes into an internal buffer. It waits for \"\\r\\n\" to determine whether a PROXY v1 line is present. If an attacker opens a TCP connection and continuously sends bytes without CRLF, Puma keeps appending to this pre-parse buffer.\n\nThis can cause unbounded in-process memory growth and additional CPU cost from repeatedly scanning the growing buffer for CRLF. A single, unauthenticated TCP connection can drive significant memory growth and may cause process/container OOM or degraded availability.\n\n**Only Puma servers using the following non-default config are affected:**\n\n```ruby\n   set_remote_address proxy_protocol: :v1\n```\n\n### Patches\n\nUsers should upgrade to versions 7.2.1 or 8.0.2.\n\n### Workarounds\n\n- Disable PROXY protocol v1 parsing if it is not required:\n\n ```ruby\n   # remove/comment this:\n   # set_remote_address proxy_protocol: :v1\n ```\n\n - Restrict direct network access to Puma listeners using PROXY protocol:\n     - Only allow trusted load balancers/reverse proxies to connect.\n     - Block arbitrary client TCP access with firewall/security group rules.\n\n### Resources\n- [HAProxy PROXY protocol specification](https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt)\n- [CWE-400: Uncontrolled Resource Consumption](https://cwe.mitre.org/data/definitions/400.html)\n- [CWE-770: Allocation of Resources Without Limits or Throttling](https://cwe.mitre.org/data/definitions/770.html)\n- [Puma `set_remote_address` documentation](https://github.com/puma/puma/blob/master/lib/puma/dsl.rb)\n- [Puma client PROXY protocol parsing code](https://github.com/puma/puma/blob/master/lib/puma/client.rb)\n- [Puma constants, including `PROXY_PROTOCOL_V1_REGEX`](https://github.com/puma/puma/blob/master/lib/puma/const.rb)",
  "id": "GHSA-qpgp-93vx-g8v8",
  "modified": "2026-11-02T22:15:04.375576543Z",
  "published": "2026-06-08T23:55:44Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/security/advisories/GHSA-qpgp-93vx-g8v8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/commit/439c6136d9c2275721b7864db3ee78af7c80889f"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/commit/ebe9db3929ab8299d19c8f5b41e8ef4f4b22fa58"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/puma/puma"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/releases/tag/v7.2.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/releases/tag/v8.0.2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/puma/CVE-2026-47736.yml"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/cve-2026-47736"
    },
    {
      "type": "WEB",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-47736"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Puma PROXY Protocol v1 Parser Allows Remote Memory Exhaustion "
}