@fastify/busboy vulnerable to Denial of Service via oversized multipart boundary

{
  "id": "1aeedd740a14359f287fe0f9f9807f34503131cb0765b35b5ba768cbc22fbe0e",
  "url": "https://osv.dev/vulnerability/CVE-2026-19484",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "@fastify/busboy vulnerable to Denial of Service via oversized multipart boundary",
    "summary": "@fastify/busboy is a multipart form-data parser. In versions 3.1.0 through 3.2.0, a remote unauthenticated attacker can stall the Node.js event loop by sending a multipart request whose boundary is crafted to a specific length. The vendored streaming search stores its skip table in a fixed 256 entry byte array, and a boundary of exactly 252 bytes makes the search needle 256 bytes, which truncates the default skip distance to zero and turns the search into a CPU bound loop on a small body. A single small request can keep one core busy and deny service to other requests handled by the same process. The issue is fixed in @fastify/busboy 3.2.1, which widens the skip table so the skip distance is preserved. Users should upgrade to 3.2.1.",
    "evidence": "osv:CVE-2026-19484",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-19484",
      "aliases": [
        "CVE-2026-19484",
        "GHSA-xjh9-v7x6-24jw"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/fastify/busboy",
              "type": "GIT",
              "events": [
                {
                  "introduced": "be7065f4e663a89a7c0006841fd1fb59dabfe4ca"
                },
                {
                  "fixed": "b404d602fe173809e5e71bf0b46132c656844047"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "3.1.0"
                      },
                      {
                        "fixed": "3.2.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "cpe": "cpe:2.3:a:fastify:fastify\\/busyboy:*:*:*:*:*:node.js:*:*",
                    "range": [
                      {
                        "introduced": "3.1.0"
                      },
                      {
                        "fixed": "3.2.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v3.2.0",
            "v3.1.1",
            "v3.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-19484.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:40.251965380Z",
      "provider": "osv",
      "references": [
        "https://cna.openjsf.org/security-advisories.html",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19484.json",
        "https://github.com/fastify/busboy/security/advisories/GHSA-xjh9-v7x6-24jw",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-19484"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-1322",
          "CWE-835"
        ],
        "cna_assigner": "openjs",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19484.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-19484",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 507561,
  "published_at": "2026-08-13T08:50:47.361+00:00"
}