CVE-2025-31137
HIGHReact Router 7.0.0-7.4.0 and Remix 2.11.1-2.16.2 - HTTP Request Smuggling via Host Header
Title source: llmExploitation Summary
EIP tracks 1 public exploit for CVE-2025-31137. PoCs published by pouriam23.
AI-analyzed exploit summary This repository provides a working proof-of-concept for CVE-2025-31137, a vulnerability in Remix React Router. It includes a CTF setup to exploit the vulnerability, requiring manual modification of the @remix-run/express package to a vulnerable version.
Description
React Router is a multi-strategy router for React bridging the gap from React 18 to React 19. There is a vulnerability in Remix/React Router that affects all Remix 2 and React Router 7 consumers using the Express adapter. Basically, this vulnerability allows anyone to spoof the URL used in an incoming Request by putting a URL pathname in the port section of a URL that is part of a Host or X-Forwarded-Host header sent to a Remix/React Router request handler. This issue has been patched and released in Remix 2.16.3 and React Router 7.4.1.
Exploits (1)
This repository provides a working proof-of-concept for CVE-2025-31137, a vulnerability in Remix React Router. It includes a CTF setup to exploit the vulnerability, requiring manual modification of the @remix-run/express package to a vulnerable version.
References (1)
Scores
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H