{"cve":"CVE-2026-19484","nvd":{"published":"2026-08-13T10:17:11.640","modified":"2026-09-03T19:10:52.893","status":"Analyzed","description":"@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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-835","CWE-1322"],"references":["https://cna.openjsf.org/security-advisories.html","https://github.com/fastify/busboy/security/advisories/GHSA-xjh9-v7x6-24jw"],"products":["fastify:fastify\\/busyboy"],"source":"nvd","synced_at":"2026-10-19T22:48:17.459049833+00:00"},"epss":{"cve":"CVE-2026-19484","score":0.00615,"percentile":0.49453,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-xjh9-v7x6-24jw","url":"https://osv.dev/vulnerability/GHSA-xjh9-v7x6-24jw","summary":"@fastify/busboy vulnerable to Denial of Service via oversized multipart boundary","modified":"2026-10-02T23:30:05.674605566Z","packages":[{"ecosystem":"npm","name":"@fastify/busboy","purl":"pkg:npm/%40fastify/busboy","ranges":[">=3.1.0 <3.2.1"],"fixed":["3.2.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}