CVE-2026-77063 (GCVE-0-2026-77063)

Vulnerability from cvelistv5 – Published: 2026-08-28 19:54 – Updated: 2026-08-28 19:54
VLAI
Title
multer vulnerable to file size limit bypass via async fileFilter race condition
Summary
multer is a middleware for handling multipart/form-data in Node.js. When an application uses an asynchronous fileFilter together with the fileSize limit, a race condition in multer's file stream handling can allow a file that exceeds the configured size limit to bypass the size-limit rejection. All versions before 2.3.0 are affected. The impact is limited because the underlying multipart parser still truncates the stream at the size limit, so this is a bypass of the limit rejection rather than uncontrolled resource consumption. The issue is fixed in multer 2.3.0. Upgrade to multer 2.3.0 to remediate.
CWE
  • CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
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.
Show details on NVD website

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