Critical Next.js ImageResponse Flaw Can Lead to Server Code Execution via Crafted SVG Input
Sep 23, 2026
Vulnerability / Web Security
A new security vulnerability in Next.js could allow attackers to run code on a server via ImageResponse , the feature that generates Open Graph and other social preview images, Vercel said. The risk applies when an app puts values an attacker controls, such as text read from the request URL, into the image. Vercel, which develops Next.js, fixed the flaw on September 22 in version 16.3.6. The flaw, tracked as CVE-2026-94545 , affects Next.js 16.2.0 through 16.3.5 when ImageResponse runs on the Node.js runtime, which Next.js uses by default . Vercel's advisory rates it critical, with a CVSS score of 9.5. The Edge version of ImageResponse is not affected, and neither is Next.js 15. ImageResponse uses Satori , a Vercel library, to convert the image layout into SVG code before the final PNG is generated. Affected apps are those that "pass attacker-controlled values into SVG content, attributes, or styles during image generation", according to ...