CVE-2025-4366

A request smuggling vulnerability identified within Pingora’s proxying framework, pingora-proxy, allows malicious HTTP requests to be injected via manipulated request bodies on cache HITs, leading to unauthorized request execution and potential cache poisoning. ### Fixed in https://github.com/cloudflare/pingora/commit/fda3317ec822678564d641e7cf1c9b77ee3759ff ### Impact The issue could lead to request smuggling in cases where Pingora’s proxying framework, pingora-proxy, is used for caching allowing an attacker to manipulate headers and URLs in subsequent requests made on the same HTTP/1.1 connection.

Pingora versions prior to 0.5.0 which used the caching functionality in pingora-proxy did not properly drain the downstream request body on cache hits. This allows an attacker to craft malicious HTTP/1.1 requests which could lead to request smuggling or cache poisoning. This flaw was corrected in commit fda3317ec822678564d641e7cf1c9b77ee3759ff by ensuring that the downstream request body is always drained before a connection can be reused. See [the blog post](https://blog.cloudflare.com/resolving-a-request-smuggling-vulnerability-in-pingora/) for more information.