multer vulnerable to Denial of Service via file descriptor leak on aborted uploads
Published 8 Sept 2026 · Updated 8 Sept 2026
Affected package
- Affected
- >=2.2.0 <2.3.0
- Fixed in
- 2.3.0
npm install multer@2.3.0Details
Impact
A vulnerability in multer 2.2.0 allows an attacker to trigger a Denial of Service (DoS) by aborting or truncating multipart uploads. When using diskStorage, the destination write stream is not closed if the upload is aborted before it finishes, so each failed request leaks an open file descriptor and retains its disk blocks until the process exits. Repeated failed uploads can exhaust the available file descriptors. All applications using multer's disk storage are affected.
Patches
Users should upgrade to 2.3.0.
Workarounds
None.
Is GHSA-qfvm-cv95-jqjf in any of your client repos?
Checking one package by hand is fine. Checking it across forty client projects is not. NPMscan reads the lockfiles in every GitHub repo you pick, finds each project with an affected multer, and gives you the command that fixes it.
References
- Linkgithub.com/expressjs/multer/security/advisories/GHSA-qfvm-cv95-jqjf
- Advisorynvd.nist.gov/vuln/detail/CVE-2026-77037
- Linkgithub.com/expressjs/multer/commit/eef74440b491ef0f976f3d25895e8089ae495df0
- Linkcna.openjsf.org/security-advisories.html
- Packagegithub.com/expressjs/multer
- Linkgithub.com/expressjs/multer/releases/tag/v2.3.0
Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.