Fastify: >> Fastify-Multipart Security Vulnerabilities
@fastify/multipart is a multipart form-data parser for Fastify. In versions from 5.3.0 up to but not including 10.1.1, when the busboy fileSize limit truncates a file part, the plugin clears its internal current-file reference while the underlying stream is still open. If the client then aborts the connection before sending the terminating boundary, the abort cleanup finds no stream to destroy, so saveRequestFiles() never settles, the request handler hangs, and the temporary file already written to disk is never cleaned up. An unauthenticated client can repeat this to permanently leak temporary files and suspended handler executions, leading to disk and event-loop exhaustion. The issue is fixed in @fastify/multipart 10.1.1. Users should upgrade to 10.1.1.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-08-15
@fastify/multipart is a multipart form-data parser for Fastify. In versions from 3.0.0 up to but not including 10.1.1, request.saveRequestFiles() can leave completed temporary files on disk when a client disconnects while the parser is advancing between multipart parts. The iterator rejection that occurs between parts falls outside the per-file cleanup path, so an earlier completed file is never removed. An unauthenticated client can repeat this to cause persistent, linear disk consumption, leading to denial of service. This is an incomplete-fix variant of CVE-2025-24033. The issue is fixed in @fastify/multipart 10.1.1. Users should upgrade to 10.1.1.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-08-15
@fastify/multipart is a Fastify plugin to parse the multipart content-type. Prior to versions 7.4.1 and 6.0.1, @fastify/multipart may experience denial of service due to a number of situations in which an unlimited number of parts are accepted. This includes the multipart body parser accepting an unlimited number of file parts, the multipart body parser accepting an unlimited number of field parts, and the multipart body parser accepting an unlimited number of empty parts as field parts. This is fixed in v7.4.1 (for Fastify v4.x) and v6.0.1 (for Fastify v3.x). There are no known workarounds.
CVSS Score
7.5
EPSS Score
0.015
Published
2023-02-14
This affects the package fastify-multipart before 5.3.1. By providing a name=constructor property it is still possible to crash the application. **Note:** This is a bypass of CVE-2020-8136 (https://security.snyk.io/vuln/SNYK-JS-FASTIFYMULTIPART-1290382).
CVSS Score
7.5
EPSS Score
0.02
Published
2022-02-11
Prototype pollution vulnerability in fastify-multipart < 1.0.5 allows an attacker to crash fastify applications parsing multipart requests by sending a specially crafted request.
CVSS Score
7.5
EPSS Score
0.015
Published
2020-03-20