CVE-2026-118659
HIGH
MEDIUM
Priority: 0.03
BB Relevance:
75/100
Published: 2026-10-28
Modified: 2026-10-29
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
Conf. Impact
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
Unchanged
C:
High
I:
None
A:
None
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.
Weakness Classification (1)
Affected Software (2)
| Vendor | Product | Version |
|---|---|---|
| capricorn86 | happy-dom | < 21.0.2 |
| capricorn86 | happy-dom | < 21.0.2 |