expressjs/multer · Security

multer vulnerable to Denial of Service via crafted multipart field names

GHSA ID
GHSA-wc9g-mqfw-jrwm
CVE ID
CVE-2026-77078
Severity
high
Published
Updated
CVSS
7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v3
7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

Impact

A vulnerability in multer allows a remote, unauthenticated attacker to crash the Node.js process with a single multipart/form-data request. Two specially crafted text field names cause an uncaught RangeError: Invalid array length inside multer's field parsing, which is not routed to the application error handler and terminates the process. All applications using multer to parse multipart requests are affected.

Patches

Users should upgrade to 2.3.0.

Workarounds

None.

CWEs

References