Uncaught Exception in multer - CVE-2026-77078
Published: September 2, 2026
Vulnerability identifier: #VU146779
CSH Severity: Medium
CVSS v4: 8.7 [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]
CVE-ID: CVE-2026-77078
CWE-ID: CWE-248
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an uncaught exception in multer field parsing when processing a crafted multipart/form-data request. A remote attacker can send specially crafted text field names to cause a denial of service.
A single multipart/form-data request can trigger a RangeError: Invalid array length that terminates the Node.js process instead of being routed to the application error handler.
Affected software
multer
How to mitigate CVE-2026-77078
Install security update from vendor's website.
multer - update to 2.3.0