CVE-2026-44578 Details.
Next.js WebSocket Upgrade Handler - SSRF
Atlas does not check this one. Not a plain web check.
This weakness is not found through ordinary web pages. It needs a different kind of connection to the service. Atlas only runs plain web, DNS and TLS checks, so it does not run this one.
About CVE-2026-44578. What It Means.
Next.js 13.4.13 to before 15.5.16 and 16.2.5 contains a server-side request forgery caused by crafted WebSocket upgrade requests in the built-in Node.js server, letting attackers proxy requests to arbitrary destinations, exploit requires self-hosted deployment.
Affected Product. What Is Hit.
- Vendor
- vercel
- Product
- Vercel Nextjs
FAQ
Common Questions.
Next.js WebSocket Upgrade Handler - SSRF. Next.js 13.4.13 to before 15.5.16 and 16.2.5 contains a server-side request forgery caused by crafted WebSocket upgrade requests in the built-in Node.js server, letting attackers proxy requests to arbitrary destinations, exploit requires self-hosted deployment.
No. This weakness is not found through ordinary web pages. It needs a different kind of connection to the service. Atlas only runs plain web, DNS and TLS checks, so it does not run this one. The facts about CVE-2026-44578 are on this page, and you can request a demo to see how Brandefense watches your whole external attack surface.
CVE-2026-44578 is not on the CISA Known Exploited Vulnerabilities list at the time of writing, but it is still worth fixing.
Update Vercel Nextjs to the latest version from the vendor, or follow the vendor's advice to switch off the affected feature. Vendor links are listed on this page when they are known.
This page lists the public facts about CVE-2026-44578. Atlas does not run a check for it, so nothing here says whether a particular site is affected.