CVE-2026-77037multer vulnerable to Denial of Service via file descriptor leak on aborted uploads
Updated under an hour ago ()
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It affects multer and 1 other product. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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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.
- CVSS
- 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- CWE-400, CWE-459
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- openjs
- NVD analysis
- Analyzed
- Record last updated
- Aug 31, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
multer multer multer:multer (from the name) | from 2.2.0 before 2.3.0; 2.3.0 not affected | CNA record |
expressjs multer expressjs:multer | 2.2.0 | NVD |
References
- https://github.com/expressjs/multer/security/advisories/GHSA-qfvm-cv95-jqjfvendor-advisory
- https://cna.openjsf.org/security-advisories.htmlvendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.