A flaw in Node.js 20's HTTP parser allows improper termination of HTTP/1 headers using "\r\n\rX" instead of the required "\r\n\r\n". This inconsistency enables request smuggling, allowing attackers to bypass proxy-based access controls and submit unauthorized requests. The issue was resolved by upgrading "llhttp" to version 9, which enforces correct header termination. Impact: * This vulnerability affects only Node.js 20.x users prior to the "llhttp" v9 upgrade.