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CVE-2026-3520

Multer vulnerable to Denial of Service via uncontrolled recursion

Published: Mar 4, 2026Updated: Jul 15, 2026 Sources: CVE List NVD GHSACWE-674
7.5HIGH
NVD MITRE
EPSS Score
0.7%
Top 49.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-674CWE-770

Affected Products

expressjs
oss-projectaka express
multerLibrary
OSS Libraries / web-framework
npm
package-ecosystem
multer
OSS Libraries

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://github.com/expressjs/multer/security/advisories/GHSA-5528-5vmv-3xc2
github.com
https://www.cve.org/CVERecord?id=CVE-2026-3520
cve.org
https://github.com/expressjs/multer/commit/7e66481f8b2e6c54b982b34c152479e096ce2752
github.com
and 8 more references View all →

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