GHSA-q7qp-rjg7-q26m
multer vulnerable to Denial of Service via a pending asynchronous fileFilter after request teardown
Packages
Details
As written in the advisory (Markdown source, shown as plain text).
### Impact
When `multer` is configured with an asynchronous `fileFilter`, a single request can crash the Node.js process. If a request is aborted (for example when one file is rejected) while another file's async `fileFilter` is still pending, the pending callback later resumes a parsing stream that multer has already torn down. busboy then emits an error on a stream that no longer has an error listener, which Node raises as an unhandled `'error'` event, and the process exits. A single unauthenticated request is enough, so any application using `multer` with an asynchronous `fileFilter` is affected, regardless of storage engine. Uploads using a synchronous `fileFilter` are not affected.
### Patches
Users should upgrade to `multer` `2.5.0` or later.
### Workarounds
Use a synchronous `fileFilter`.
References
External links from the advisory. They lead to third-party sites.
- https://github.com/expressjs/multer/security/advisories/GHSA-q7qp-rjg7-q26m
- https://nvd.nist.gov/vuln/detail/CVE-2026-113872
- https://github.com/expressjs/multer/commit/80a2d9df1dfd63b5fab631b8b9966164ed647adf
- https://cna.openjsf.org/security-advisories.html
- https://github.com/expressjs/multer
- https://github.com/expressjs/multer/releases/tag/v2.5.0