myxce/.wolf/bugs/bug-1948.md

id	status	status_updated	status_note	component	severity	timestamp	last_seen	occurrences	files	tags	related	fix_commits	gitea_issue	gitea_synced_status	gitea_synced_hash
bug-1948	fixed	2026-10-10		apiserver	security	2026-10-10T08:15:06Z	2026-10-10T08:15:06Z	1	src/frontend/apiserver/router/routers.go	apiserver security whitelist		c4c63f11	379	fixed	c922e7fd47f6

bug-1948: apiserver trusts X-Forwarded-For from any client, so IP whitelist and JWT IP binding can be spoofed

Description

Observed: (source reading, .kiro/reviews/project-gap-review-2026-10-10.md (P0); to be confirmed by a failing test before the fix) The router uses gin.Default() (router/routers.go:19) and never calls SetTrustedProxies, so ClientIP() honours X-Forwarded-For from any peer.

Expected: Forwarded headers are only honoured from configured trusted proxies. Impact: Security: a client can claim any IP and bypass the IP whitelist and the IP bound into its JWT. Found by: review: .kiro/reviews/project-gap-review-2026-10-10.md (P0)

Environment

• OS: no /etc/os-release; Docker container; NixOS kernel; kernel Linux 6.18.33 x86_64
• libc: glibc 2.42-47 (interpreter /nix/store/wb6rhpznjfczwlwx23zmdrrw74bayxw4-glibc-2.42-47/lib/ld-linux-x86-64.so.2)
• Toolchain: gcc (GCC) 15.2.0, meson 1.9.1
• Build: asan (xce.build)
• Code: scheduler-framework @ 94472ee3-dirty
• Deployment: any (found by source reading; the failing test that confirms it is named in Verification)

Reproduction

1. Send a request with X-Forwarded-For: <whitelisted IP> from a non-whitelisted host.
2. It passes the whitelist.

• Frequency: deterministic (by code reading; confirmed by the RED test of the fix)
• Evidence: the code sites quoted in Description; no logs kept.

Root cause

router.Router() used gin.Default() without SetTrustedProxies, so ClientIP() honoured X-Forwarded-For from any peer.

Fix

New app.yaml option security.trusted_proxies (IP/CIDR, default empty = none), validated at startup; Router() passes it to SetTrustedProxies (falls back to none if invalid); schema and nginx samples documented.

Verification

• Test: TestRouter_IgnoresForwardedForByDefault (router/routers_test.go, real Router()): RED non-whitelisted peer spoofing X-Forwarded-For: status = 200, want 403, GREEN after; plus TestRouter_HonoursForwardedForFromTrustedProxy, TestResolveTrustedProxies.
• Suites: xce-build.sh all asan xce.build --incremental on the merged branch, 2026-10-10: all C suites Ok 155 / Fail 0, frontend Go unit tests ok, xceadmin tests ok; apiserver CGO_ENABLED=0 go test ./... (incl. middleware, router, cmd) ok
• Live: n/a: unit/fixture-level verification only; no live deployment was run (follow-up)

References

• Fix commit: c4c63f11 (on scheduler-framework; worker-branch original in the merge)
• Review: .kiro/reviews/project-gap-review-2026-10-10.md