1Panel is an open-source, web-based control panel for Linux server management. Versions 2.0.14 and below use Gin's default configuration which trusts all IP addresses as proxies (TrustedProxies = 0.0.0.0/0), allowing any client to spoof the X-Forwarded-For header. Since all IP-based access controls (AllowIPs, API whitelists, localhost-only checks) rely on ClientIP(), attackers can bypass these protections by simply sending X-Forwarded-For: 127.0.0.1 or any whitelisted IP. This renders all IP-based security controls ineffective. This issue is fixed in version 2.0.14.

1Panel IP Access Control Bypass via Untrusted X-Forwarded-For Headers