Multer vulnerable to Denial of Service via memory leaks from unclosed streams
Impact
Multer <2.0.0 is vulnerable to a resource exhaustion and memory leak issue due to improper stream handling. When the HTTP request stream emits an error, the internal busboy stream is not closed, violating Node.js stream safety guidance.
This leads to unclosed streams accumulating over time, consuming memory and file descriptors. Under sustained or repeated failure conditions, this can result in denial of service, requiring manual server restarts to recover. All users of Multer handling file uploads are potentially impacted.
Patches
Users should upgrade to 2.0.0
Workarounds
None
References
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | multer | < 2.0.0 | 2.0.0 |
References
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness (CWE)
CWE-401- Platform
- npm
- Package
multer- Disclosed
- 19.05.2025
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-44fp-w29j-9vj5 - CC BY 4.0
Vulnerability history: multer
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 14
- First → latest
- 05.2025 09.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- High 11
- Medium 2
- Low 1
Disclosures per year
- 2025: 4
- 2026: 10
-
Multer vulnerable to Denial of Service via memory leaks from unclosed streams this entry
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