CVE-2026-3304

HIGH

Multer < 2.1.0 - Denial of Service via Malformed Request Handling

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-3304. PoCs published by Mkway.

AI-analyzed exploit summary This repository contains a functional exploit PoC for CVE-2026-3304, a DoS vulnerability in Multer < 2.1.0 caused by incomplete cleanup of temporary files when processing malformed multipart requests. The exploit includes a Dockerized lab environment, curl-based PoC, and Python script to demonstrate disk exhaustion via orphaned files.

Description

Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.0 allows an attacker to trigger a Denial of Service (DoS) by sending malformed requests, potentially causing resource exhaustion. Users should upgrade to version 2.1.0 to receive a patch. No known workarounds are available.

Exploits (1)

nomisec WORKING POC
by Mkway · poc
https://github.com/Mkway/CVE-2026-3304

This repository contains a functional exploit PoC for CVE-2026-3304, a DoS vulnerability in Multer < 2.1.0 caused by incomplete cleanup of temporary files when processing malformed multipart requests. The exploit includes a Dockerized lab environment, curl-based PoC, and Python script to demonstrate disk exhaustion via orphaned files.

Classification
Working Poc 100%
Attack Type
Dos
Complexity
Trivial
Reliability
Reliable
Target: Multer < 2.1.0 (Node.js multipart/form-data middleware)
No auth needed
Prerequisites: Docker · Python 3 with requests library
devstral-2 · analyzed Mar 06, 2026 Full analysis →

References (4)

Core 4

Scores

CVSS v3 7.5
EPSS 0.0002
EPSS Percentile 5.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-459
Status published
Products (3)
expressjs/multer < 2.1.0
expressjs/multer 0.0.0 - 2.1.0
npm/multer 0 - 2.1.0npm
Published Feb 27, 2026
Tracked Since Feb 27, 2026