Skip to main content
← All vulnerabilities
CVE-2026-118659EUVD-2026-112466GHSA-PMF4-3XR3-XJHG

@happy-dom/server-renderer: ServerRendererServer Target-Origin Bypass SSRF / Open Proxy

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 21.0.2
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: poc
  • Automatable: yes
  • Technical impact: partial

Summary

The @happy-dom/server-renderer package (part of the Happy DOM JavaScript browser implementation) is affected. Its server accepts unauthenticated requests and can be tricked into fetching arbitrary HTTP or HTTPS addresses, including internal services reachable from the server, and then returns those responses to the requester.

Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.

Read the original description

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.2, the Happy DOM server-renderer package's ServerRendererServer accepts unauthenticated HTTP/2 requests and resolves attacker-controlled :path values against server.targetOrigin in #onIncomingRequest in packages/@happy-dom/server-renderer/src/ServerRendererServer.ts without confirming that the resolved origin remains trusted before calling fetch. A protocol-relative path can change the destination to an arbitrary HTTP or HTTPS endpoint reachable by the server, including local and internal services, and the proxy relays the fetched response headers and body to the requester. This issue is fixed in version 21.0.2.

Timeline

  1. CVE published
  2. First seen by cve.now
  3. CISA SSVC assessment

    Exploitation: poc · Automatable: yes · Technical impact: partial

  4. Record last updated

Affected versions

  • capricorn86 happy-dom

    fixed in 21.0.2

References 4

GitHub · capricorn86/happy-dom