CVE-2026-3520
High
Description
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.
SeverityHigh
CVSS7.5
Exploit probability—
ProductExpressjs Multer
PublishedMar 4, 2026
First seenMar 4, 2026
Weakness typeCWE-674CWE-674
How to fix
Update
- expressjs multer2.1.1 or later
- multer2.1.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| expressjs multer | v < 2.1.1 | 2.1.1 |
| multernpm | v < 2.1.1 | 2.1.1 |
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