Input validation error in Next.js - CVE-2026-119347
Published: November 4, 2026
Vulnerability identifier: #VU159257
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-119347
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass SVG processing restrictions and potentially cause a denial of service.
The vulnerability exists due to improper input validation in the Next.js image optimizer (/_next/image) when handling attacker-supplied images. A remote attacker can submit an SVG image that bypasses rejection even when dangerouslyAllowSVG is false, reaching the disabled SVG parser and potentially causing a denial of service.
The issue affects self-hosted deployments.
Affected software
Next.js
How to mitigate CVE-2026-119347
Install security update from vendor's website.
Next.js - addressed in versions 1.0.0, 1.0.1, 1.0.2, 1.1.0, 1.1.1, 1.1.2, 1.2.0, 1.2.1, 1.2.2, 1.2.3, 2.0.0, 2.0.1, 2.1.0, 2.1.1, 2.2.0, 2.3.0, 2.3.1, 2.3.2, 2.4.0, 7.0.0.0, 7.0.1.0, 15.5.29, 16.4.5