CVE-2026-82333 (GCVE-0-2026-82333)

Vulnerability from cvelistv5 – Published: 2026-08-28 20:12 – Updated: 2026-08-31 18:39
VLAI
Title
multer vulnerable to Denial of Service via oversized array index in field names
Summary
multer is a middleware for handling multipart/form-data in Node.js. A small multipart request with two specially crafted text field names can make multer's field parser synchronously iterate a maximum-length sparse array, blocking the event loop so the process cannot handle other requests. A large numeric array index in the first field allocates a maximum-length sparse array, and a second field with a non-numeric key then triggers a full-length iteration inside the append-field dependency. All versions before 2.3.0 are affected, and this is a remotely triggerable denial of service. multer 2.3.0 adds an opt-in fieldArrayIndexLimit option that rejects oversized array indexes. Upgrade to multer 2.3.0 and set limits.fieldArrayIndexLimit to the largest array index your application needs 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 18:39 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
openjs CNA under the redhat root
CNA scorecard C 65/100 over 99 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 arpitjain099
Show details on NVD website
To clipboard 

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