CVE-2026-23870: React server dom parcel Denial of Service Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rv78-f8rc-xrxh",
  "modified" : "2026-05-11T14:50:07Z",
  "published" : "2026-05-11T14:50:07Z",
  "aliases" : [ "CVE-2026-23870" ],
  "summary" : "Facebook React has a Denial of Service Vulnerability in React Server Components",
  "details" : "## Impact\n\nA denial of service vulnerability could be triggered by sending specially crafted HTTP requests to server function endpoints, this could lead to out-of-memory exceptions or excessive CPU usage.\n\nWe recommend updating immediately.\n\nThe vulnerability exists in versions 19.0.0 through 19.0.5, 19.1.0 through 19.1.6, and 19.2.0 through 19.2.5 of:\n\n[react-server-dom-webpack](https://www.npmjs.com/package/react-server-dom-webpack)\n[react-server-dom-parcel](https://www.npmjs.com/package/react-server-dom-parcel)\n[react-server-dom-turbopack](https://www.npmjs.com/package/react-server-dom-turbopack?activeTab=readme)\n\n## Patches\n\nFixes were back ported to versions 19.0.6, 19.1.7, and 19.2.6.\n\nIf you are using any of the above packages please upgrade to any of the fixed versions immediately.\n\nIf your app’s React code does not use a server, your app is not affected by this vulnerability. If your app does not use a framework, bundler, or bundler plugin that supports React Server Components, your app is not affected by this vulnerability.\n\nReferences\nSee the [blog post](https://react.dev/blog/2025/12/11/denial-of-service-and-source-code-exposure-in-react-server-components) for more information and upgrade instructions.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-parcel"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.0.0"
      }, {
        "fixed" : "19.0.6"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-turbopack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.0.0"
      }, {
        "fixed" : "19.0.6"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-webpack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.0.0"
      }, {
        "fixed" : "19.0.6"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-parcel"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.1.0"
      }, {
        "fixed" : "19.1.7"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-turbopack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.1.0"
      }, {
        "fixed" : "19.1.7"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-webpack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.1.0"
      }, {
        "fixed" : "19.1.7"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-parcel"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.2.0"
      }, {
        "fixed" : "19.2.6"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-turbopack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.2.0"
      }, {
        "fixed" : "19.2.6"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "react-server-dom-webpack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "19.2.0"
      }, {
        "fixed" : "19.2.6"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/facebook/react/security/advisories/GHSA-rv78-f8rc-xrxh"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vercel/next.js/security/advisories/GHSA-8h8q-6873-q5fj"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vitejs/vite-plugin-react/security/advisories/GHSA-w94c-4vhp-22gx"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-23870"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/facebook/react"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-400", "CWE-770" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-11T14:50:07Z",
    "nvd_published_at" : "2026-05-06T17:16:22Z"
  }
}