Multer vulnerable to Denial of Service via unhandled exception

HIGH 8.7CVE-2025-48997 · GHSA-g5hg-p3ph-g8qg · Published 03/06/2025 · updated 17/06/2026

In short

CVE-2025-48997 is a HIGH (CVSS 8.7) vulnerability affecting multer.
Chance of exploitation in the next 30 days (EPSS): 0.48%, higher than 41.6% of all vulnerabilities.
Fix: update to 2.0.1 or later.

Package	Affected versions	Patched versions
multer npm	`≥ 1.4.4-lts.1, < 2.0.1`	`2.0.1`

Description

Impact

A vulnerability in Multer versions >=1.4.4-lts.1, <2.0.1 allows an attacker to trigger a Denial of Service (DoS) by sending an upload file request with an empty string field name. This request causes an unhandled exception, leading to a crash of the process.

Patches

Users should upgrade to 2.0.1

Workarounds

None

References

https://github.com/expressjs/multer/commit/35a3272b611945155e046dd5cef11088587635e9 https://github.com/expressjs/multer/issues/1233 https://github.com/expressjs/multer/pull/1256

NVD description

Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability that is present starting in version 1.4.4-lts.1 and prior to version 2.0.1 allows an attacker to trigger a Denial of Service (DoS) by sending an upload file request with an empty string field name. This request causes an unhandled exception, leading to a crash of the process. Users should upgrade to `2.0.1` to receive a patch. No known workarounds are available.