CVE-2026-77037 (GCVE-0-2026-77037)

Vulnerability from cvelistv5 – Published: 2026-08-28 19:44 – Updated: 2026-08-31 18:41
VLAI
Title
multer vulnerable to Denial of Service via file descriptor leak on aborted uploads
Summary
multer is a middleware for handling multipart/form-data in Node.js. In version 2.2.0, when a disk-backed upload is aborted or truncated before the write stream finishes, multer's disk storage engine removes the visible file but does not close the underlying write file descriptor, leaving a deleted but still open descriptor. A remote attacker able to reach an upload route using the built-in disk storage can send repeated aborted or malformed multipart uploads, each one leaking a file descriptor and retaining disk blocks until the process exits, which can exhaust resources and cause a denial of service. The issue is fixed in multer 2.3.0, which closes the destination write stream on abnormal source termination and defers cleanup until the stream has closed. 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 18:41 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-459 - Incomplete Cleanup
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: 2.2.0 , < 2.3.0 (semver)
Unaffected: 2.3.0 (semver)
guessed Create a notification for this product.
Credits
dkoazw EmirCobanOfficial bjohansebas UlisesGascon
Show details on NVD website
To clipboard 

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