fix(webhooks): set trust proxy and resolve client IP via req.ip#427
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Both webhook servers sit behind one XFF-writing hop (nginx ingress; the
DO LB is L4). Without trust proxy, express-rate-limit keyed every sender
into one bucket on the LB socket, and the IP allowlists resolved the
client via request-ip, which prefers the leftmost X-Forwarded-For entry
— forgeable by any caller once an allowlist is enabled.
- app.set("trust proxy", 1) on the Bridge and IBEX webhook servers
- ibex.webhook.allowedIps and the Bridge replay allowlist now match on
req.ip (rightmost untrusted XFF hop) with socket-address fallback
- loopback replay exemption unchanged: socket address only
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
bobodread876
approved these changes
Jul 3, 2026
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Summary
Launch-hardening follow-up from the #413 merge (tracked as a pre-cutover deploy item).
Both the Bridge and IBEX webhook servers run behind exactly one XFF-writing hop (nginx ingress; the DO load balancer is L4). Without
trust proxy:ibex.webhook.allowedIps, Bridge replayBRIDGE_WEBHOOK_REPLAY_ALLOWED_IPS) resolved the client withrequest-ip, which prefers the leftmostX-Forwarded-Forentry — any caller can forge that to an allowlisted IP once an allowlist is enabled.Changes
app.set("trust proxy", 1)on both webhook servers (trust exactly the one ingress hop; client-forged XFF entries stay untrusted).req.ip(rightmost untrusted XFF entry) with a socket-address fallback, replacingrequest-ipinvalidateIbexIpandreplayIngressMiddleware.validate: { xForwardedForHeader: false }on the limiters as a safety net: a future trust-proxy misconfiguration degrades to a shared bucket instead of a webhook outage.Testing
TEST=webhook-server npm run test:unit— 8 suites, 85 tests pass (replay ingress specs updated to thereq.ipsemantics, plus a new socket-fallback case).npx tsc --noEmitclean.Deploy notes
Pairs with the remaining pre-cutover config item: populate
ibex.webhook.allowedIpswith IBEX's published webhook IPs (allowlist is intentionally fail-open while empty).🤖 Generated with Claude Code