High

Multer vulnerable to Denial of Service via unhandled exception

  • Disclosed: 05.06.2025
  • Updated: 11.10.2026 10:22

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

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
npm package multer >= 1.4.4-lts.1, < 2.0.1 2.0.1

References

CVSS score -
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness (CWE)
CWE-248
Platform
npm
Package
multer
Disclosed
05.06.2025
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-g5hg-p3ph-g8qg - 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.

All (14) in the archive
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

  1. 2025: 4
  2. 2026: 10
Severity:
  1. High · 7.5 CVE-2026-5079 >= 1.0.0, < 2.2.0, >= 3.0.0-alpha.1, < 3.0.0-alpha.2 2.2.0, 3.0.0-alpha.2
  2. High · 7.5 CVE-2025-7338 >= 1.4.4-lts.1, < 2.0.2 2.0.2
  3. Multer vulnerable to Denial of Service via unhandled exception this entry
    High CVE-2025-48997 >= 1.4.4-lts.1, < 2.0.1 2.0.1
  4. High · 7.5 CVE-2025-47944 >= 1.4.4-lts.1, < 2.0.0 2.0.0

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