CVE-2026-77078 (GCVE-0-2026-77078)

Vulnerability from cvelistv5 – Published: 2026-08-28 20:03 – Updated: 2026-08-31 18:40
VLAI
Title
multer vulnerable to Denial of Service via crafted multipart field names
Summary
multer is a middleware for handling multipart/form-data in Node.js. A small multipart request containing two specially crafted text field names can cause an uncaught RangeError (Invalid array length) that terminates the Node.js process. The first field uses a very large numeric array index to allocate a maximum-length sparse array, and a second field then pushes past that length, which throws inside the append-field dependency and is not caught by multer. All versions before 2.3.0 are affected, and the issue is a remotely triggerable denial of service. The issue is fixed in multer 2.3.0. Upgrade to multer 2.3.0 to remediate.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-31 18:40 UTC
CWE
Assigner
openjs CNA under the redhat root
CNA scorecard C 66/100 over 142 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
multer multer Affected: 0 , < 2.3.0 (semver)
Unaffected: 2.3.0 (semver)
guessed Create a notification for this product.
Credits
O4FDev UlisesGascon
Show details on NVD website
To clipboard 

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