CVE-2025-48865

CVE-2025-48865 is a critical vulnerability affecting Fabio, an HTTP(S) and TCP router, prior to version 1.6.6. It allows malicious HTTP clients to remove or manipulate X-Forwarded headers (excluding X-Forwarded-For) by exploiting how Fabio processes hop-by-hop headers, potentially leading to security vulnerabilities in backend applications that trust these headers. Rated with a CVSS score of 9.1 (CRITICAL), this vulnerability has a network attack vector, low attack complexity, and high impact on confidentiality and integrity, requiring no privileges or user interaction. Currently, there is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage surrounding this CVE.