CVE-2026-2359: CWE-772 in expressjs multer
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.0 allows an attacker to trigger a Denial of Service (DoS) by dropping connection during file upload, potentially causing resource exhaustion. Users should upgrade to version 2.1.0 to receive a patch. No known workarounds are available.
AI Analysis
Technical Summary
The vulnerability in Multer (expressjs middleware) before version 2.1.0 is classified as CWE-772 and allows an attacker to trigger a Denial of Service by dropping the connection during file upload. This behavior can cause resource exhaustion on the server handling the file uploads. The CVSS 4.0 score is 8.7 (high severity), indicating network attack vector, no privileges or user interaction required, and high impact on availability. The vendor advisory from Red Hat confirms the issue and recommends upgrading to version 2.1.0. No alternative mitigations or workarounds are provided.
Potential Impact
Successful exploitation results in Denial of Service due to resource exhaustion caused by interrupted file uploads. This impacts availability of services relying on Multer for multipart/form-data processing. There is no indication of confidentiality or integrity impact. The vulnerability can be exploited remotely without authentication or user interaction.
Mitigation Recommendations
Upgrade Multer to version 2.1.0 or later, which contains the official fix for this vulnerability. No known workarounds exist. Users should apply this update promptly to prevent potential Denial of Service attacks.
CVE-2026-2359: CWE-772 in expressjs multer
Description
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.0 allows an attacker to trigger a Denial of Service (DoS) by dropping connection during file upload, potentially causing resource exhaustion. Users should upgrade to version 2.1.0 to receive a patch. No known workarounds are available.
CVSS v4.0
Score 8.7high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in Multer (expressjs middleware) before version 2.1.0 is classified as CWE-772 and allows an attacker to trigger a Denial of Service by dropping the connection during file upload. This behavior can cause resource exhaustion on the server handling the file uploads. The CVSS 4.0 score is 8.7 (high severity), indicating network attack vector, no privileges or user interaction required, and high impact on availability. The vendor advisory from Red Hat confirms the issue and recommends upgrading to version 2.1.0. No alternative mitigations or workarounds are provided.
Potential Impact
Successful exploitation results in Denial of Service due to resource exhaustion caused by interrupted file uploads. This impacts availability of services relying on Multer for multipart/form-data processing. There is no indication of confidentiality or integrity impact. The vulnerability can be exploited remotely without authentication or user interaction.
Mitigation Recommendations
Upgrade Multer to version 2.1.0 or later, which contains the official fix for this vulnerability. No known workarounds exist. Users should apply this update promptly to prevent potential Denial of Service attacks.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- openjs
- Date Reserved
- 2026-02-11T17:10:23.973Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-2359","vendor":"Red Hat"},{"url":"https://access.redhat.com/errata/RHSA-2026:6174","vendor":"Red Hat"},{"url":"https://access.redhat.com/errata/RHSA-2026:6802","vendor":"Red Hat"}]
Threat ID: 69a1be9b32ffcdb8a23e7057
Added to database: 02/27/2026, 15:56:11 UTC
Last enriched: 07/15/2026, 08:49:41 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 265
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