Don't trust proxy headers for client IP#1492
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The device is reached directly rather than behind a reverse proxy, but gin trusts all proxies by default, so c.ClientIP() returns the client-controlled X-Forwarded-For/X-Real-IP value. A caller could rotate that header to get a fresh rate-limit key on every request and bypass the login/setup throttle. Call SetTrustedProxies(nil) so ClientIP() uses the real socket peer.
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The web server runs
gin.Default()without callingSetTrustedProxies, so gin trusts every proxy by default andc.ClientIP()returns the client-controlledX-Forwarded-For/X-Real-IPvalue.The device is reached directly, not behind a reverse proxy, so those headers should never be trusted. As-is, a caller can rotate
X-Forwarded-Forto get a fresh rate-limit key on every request and bypass the throttle on/auth/login-localand/device/setup, enabling unlimited online password guessing.Fix: call
r.SetTrustedProxies(nil)soClientIP()uses the real socket peer. Also tightens the IP shown in logs/metrics.Note
Low Risk
Small, security-hardening router bootstrap change with no intended behavior change when the device is not behind a proxy; fails fast if proxy config cannot be applied.
Overview
Disables trusting proxy headers in Gin during router setup by calling
r.SetTrustedProxies(nil), with fatal logging if that configuration fails.Because the KVM web UI is reached directly (not behind a reverse proxy),
c.ClientIP()will now use the real TCP peer instead of client-controlledX-Forwarded-For/X-Real-IP. That closes a bypass where attackers could rotate forwarded IPs to evade the password rate limiter on/auth/login-localand/device/setup, and makes logs/metrics IP labels reflect the actual connection source.Reviewed by Cursor Bugbot for commit 97cab04. Bugbot is set up for automated code reviews on this repo. Configure here.