From 04e951697c2349ff15586ff046871823d1dfd62c Mon Sep 17 00:00:00 2001 From: kisfenyo Date: Thu, 1 Oct 2026 21:02:51 +0200 Subject: [PATCH] docmost: remove the client-written X-Forwarded-For chain on its router (R-753) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fastify trustProxy true — leftmost XFF; its login limit (10/min) is keyed by IP only. Once traefik trusts the tunnel's fixed address (controller v0.286.0), the leftmost entry is what a stranger writes; with the chain removed the app reads traefik's X-Real-Ip or its peer, as before — never forgeable. Measured on 9202: a router with this middleware receives no X-Forwarded-For (felhom.eu audits/visitors-2026-10-01/A/P1). Co-Authored-By: Claude Opus 5.5 (1M context) Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS --- templates/docmost/docker-compose.yml | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/templates/docmost/docker-compose.yml b/templates/docmost/docker-compose.yml index ab3f3af..3be5cce 100644 --- a/templates/docmost/docker-compose.yml +++ b/templates/docmost/docker-compose.yml @@ -49,6 +49,10 @@ services: labels: - "traefik.enable=true" - "traefik.http.routers.docmost.rule=Host(`${SUBDOMAIN}.${DOMAIN}`)" + # R-753: this app reads the LEFTMOST X-Forwarded-For entry, which a stranger writes once traefik keeps the + # tunnel's chain — so its chain is removed here (it then reads traefik's X-Real-Ip or peer; never forgeable). + - "traefik.http.middlewares.docmost-xff.headers.customrequestheaders.X-Forwarded-For=" + - "traefik.http.routers.docmost.middlewares=docmost-xff" - "traefik.http.routers.docmost.entrypoints=websecure" - "traefik.http.routers.docmost.tls=true" - "traefik.http.routers.docmost.tls.certresolver=letsencrypt"