CVE-2026-33805 @fastify/reply-from vulnerable to connection header abuse enabling stripping of proxy-added headers

@fastify/reply-from v12.6.1 and earlier and @fastify/http-proxy v11.4.3 and earlier process the client's Connection header after the proxy has added its own headers via rewriteRequestHeaders. This allows attackers to retroactively strip proxy-added headers from upstream requests by listing them i...

fastify/reply-from和fastify/http-proxy 安全漏洞

fastify/reply-from and fastify/http-proxy are both products from the Fastify open-source project. fastify/reply-from is a plugin designed to forward incoming HTTP requests to another server. fastify/http-proxy is a full-featured HTTP proxy plugin that supports proxying WebSocket connections and...

CVE-2026-33805: Improper Neutralization of HTTP Headers for Scripting Syntax

@fastify/reply-from v12.6.1 and earlier and @fastify/http-proxy v11.4.3 and earlier process the client's Connection header after the proxy has added its own headers via rewriteRequestHeaders. This allows attackers to retroactively strip proxy-added headers from upstream requests by listing them i...

PT-2026-33038

Name of the Vulnerable Software and Affected Versions @fastify/reply-from versions prior to 12.6.2 @fastify/http-proxy versions prior to 11.4.4 Description An issue exists where the client's Connection header is processed after the proxy has added its own headers via rewriteRequestHeaders. This...

Improper Access Control

fastify-reply-from is vulnerable to Improper Access Control. The vulnerability is due to insufficient validation of forwarded URLs in reply.from, which allows an attacker to craft malicious URLs and access unauthorized routes...

CVE-2025-66415

A flaw was found in fastify-reply-from. This vulnerability allows an attacker to bypass intended route restrictions and gain unauthorized access to specific application routes, potentially exposing sensitive information or functionality, via crafting a malicious Uniform Resource Locator URL...

EUVD-2025-200117

fastify-reply-from affected by bypass of reply forwarding...

Directory Traversal

Overview @fastify/reply-from is a forward your HTTP request to another server, for fastify Affected versions of this package are vulnerable to Directory Traversal via the reply.from function. An attacker can access unauthorized routes by crafting a malicious URL containing encoded directory...

fastify-reply-from affected by bypass of reply forwarding

Summary By crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. Details An attacker can bypass the route defined by the @fastify/reply-from package by adding a .. symbol, which, for curl...

GHSA-2Q7R-29RG-6M5H fastify-reply-from affected by bypass of reply forwarding

Summary By crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. Details An attacker can bypass the route defined by the @fastify/reply-from package by adding a .. symbol, which, for curl...

CVE-2025-66415

fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. Prior to 12.5.0, by crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. This vulnerability is...

CVE-2025-66415

CVE-2025-66415 affects the Fastify plugin @fastify/reply-from . Affected versions allow bypassing route restrictions by crafting a malicious URL, enabling access to routes that should be disallowed when using reply.from. The vulnerability is described across multiple sources as a bypass of reply ...

CVE-2025-66415 fastify-reply-from bypass of reply forwarding

fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. Prior to 12.5.0, by crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. This vulnerability is...

CVE-2025-66415 fastify-reply-from bypass of reply forwarding

fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. Prior to 12.5.0, by crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. This vulnerability is...

CVE-2025-66415 fastify-reply-from bypass of reply forwarding

fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. Prior to 12.5.0, by crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. This vulnerability is...

CVE-2025-66415: Unintended Proxy or Intermediary

fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. Prior to 12.5.0, by crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. This vulnerability is...

PT-2025-48579

Name of the Vulnerable Software and Affected Versions fastify-reply-from versions prior to 12.5.0 Description fastify-reply-from is a Fastify plugin used to forward HTTP requests to another server. Versions of the plugin prior to 12.5.0 contain a flaw where a malicious URL can be crafted to allow...

CVE-2023-51701

fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. A reverse proxy server built with @fastify/reply-from could misinterpret the incoming body by passing an header ContentType: application/json ; charset=utf-8. This can lead to bypass of security checks...

Request Smuggling

fastify-reply-from is vulnerable to Request Smuggling. The vulnerability is due to the absence of a unified Content-Type parsing, unlike the majority of Fastify that uses fast-content-type-parse with trimming after split. This issue can be exploited by an attacker to bypass security checks,...

@fastify/reply-from JSON Content-Type parsing confusion

Impact The main repo of fastify use fast-content-type-parse to parse request Content-Type, which will trim after split. The fastify-reply-from have not use this repo to unify the parse of Content-Type, which won't trim. As a result, a reverse proxy server built with @fastify/reply-from could...