CVE-2026-54299

Astro is a web framework. Prior to 6.4.6, Astro SSR apps with prerendered error pages /404 or /500 using export const prerender = true fetch those pages over HTTP at runtime when an error occurs. The URL for this fetch is derived from request.url, which in turn gets its origin from the incoming...

Astro: Host header SSRF in prerendered error page fetch

Summary Astro SSR apps with prerendered error pages /404 or /500 using export const prerender = true fetch those pages over HTTP at runtime when an error occurs. The URL for this fetch is derived from request.url, which in turn gets its origin from the incoming Host header. When the Host header i...

EUVD-2026-7455

Astro is a web framework. Prior to version 9.5.4, Server-Side Rendered pages that return an error with a prerendered custom error page eg. 404.astro or 500.astro are vulnerable to SSRF. If the Host: header is changed to an attacker's server, it will be fetched on /500.html and they can redirect...