CVE-2026-3520 HIGH

CVE-2026-3520: Multer vulnerable to Denial of Service via uncontrolled recursion

Vendor Expressjs
Product multer
Weakness CWE-674
Published March 4, 2026
Last update June 30, 2026
View on NVD All CVEs

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.1 allows an attacker to trigger a Denial of Service (DoS) by sending malformed requests, potentially causing stack overflow. Users should upgrade to version 2.1.1 to receive a patch. No known workarounds are available.

Key dates

02Disclosure timeline

March 4, 2026 CVE published
June 30, 2026 Record updated