CVE-2025-47935

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

• https://github.com/expressjs/multer/pull/1120
• https://github.com/expressjs/multer/commit/2c8505f207d923dd8de13a9f93a4563e59933665