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.
Metrics
Affected Vendors & Products
References
History
Sat, 29 Aug 2026 00:30:00 +0000
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Multer
Multer multer |
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| Vendors & Products |
Multer
Multer multer |
Fri, 28 Aug 2026 22:00:00 +0000
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| Description | 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. | |
| Title | multer vulnerable to Denial of Service via file descriptor leak on aborted uploads | |
| Weaknesses | CWE-400 CWE-459 |
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| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: openjs
Published:
Updated: 2026-08-28T19:44:23.501Z
Reserved: 2026-08-20T09:01:08.767Z
Link: CVE-2026-77037
No data.
Status : Received
Published: 2026-08-28T22:16:53.627
Modified: 2026-08-28T22:16:53.627
Link: CVE-2026-77037
No data.
OpenCVE Enrichment
Updated: 2026-08-29T00:15:05Z