multer vulnerable to Denial of Service via incomplete cleanup of aborted uploads

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-5038
StatePUBLISHED
Assigneropenjs
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-06-15 16:16:34 UTC
Updated2026-06-16 16:59:41 UTC
DescriptionImpact: multer versions 2.0.0-alpha.1 through 2.1.1 and 3.0.0-alpha.1 are vulnerable to a Denial of Service when using diskStorage. Aborted or malformed multipart uploads leave orphaned partial files on disk because the Readable.pipe() call does not propagate the stream destroy signal to the underlying fs.WriteStream. An attacker can exhaust disk space by triggering many aborted uploads, with no application bug required. Patches: Users should upgrade to multer 2.2.0 (2.x line) or 3.0.0-alpha.2 (3.x prerelease). Both versions track in-flight write streams and clean them up on the abort path. Workarounds: None.

Risk And Classification

Primary CVSS: v3.1 7.5 HIGH from [email protected]

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS: 0.002780000 probability, percentile 0.194120000 (date 2026-06-23)

Problem Types: CWE-459 | CWE-459 CWE-459: Incomplete Cleanup

VersionSourceTypeScoreSeverityVector
3.1[email protected]Primary7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
3.1ce714d77-add3-4f53-aff5-83d477b104bbSecondary5.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
3.1CNACVSS5.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Expressjs Multer All All All All
Application Expressjs Multer 3.0.0 alpha1 All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Multer Multer affected 2.0.0-alpha.1 2.2.0 semver Not specified
CNA Multer Multer unaffected 2.2.0 semver Not specified
CNA Multer Multer affected 3.0.0-alpha.1 3.0.0-alpha.2 semver Not specified
CNA Multer Multer unaffected 3.0.0-alpha.2 semver Not specified

References

ReferenceSourceLinkTags
cna.openjsf.org/security-advisories.html ce714d77-add3-4f53-aff5-83d477b104bb cna.openjsf.org Vendor Advisory
github.com/expressjs/multer/security/advisories/GHSA-3p4h-7m6x-2hcm ce714d77-add3-4f53-aff5-83d477b104bb github.com Vendor Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: yuki-matsuhashi (en)

CNA: HamdaanAliQuatil (en)

CNA: fasrm (en)

CNA: UlisesGascon (en)

CNA: bjohansebas (en)

CNA: 0xStraw-Hat (en)

CNA: bhaswanthc (en)

CNA: ByamB4 (en)

CNA: sbouabid-sec (en)

CNA: DavidCarliez (en)

CNA: JebeenLee (en)

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report