Roadmap: MCP Security Sprint — 4 domains, 10 chantiers (DELIVERED ✅)

Status: ✅ DELIVERED — sprint closed on May 9, 2026

Update May 9, 2026 (end of session): all 10 chantiers delivered in a single marathon session, and all 3 coordinated releases published the same day (hugo-mcp v1.9.0, mcp-oauth-proxy v2.1.0, mcp-installer v1.3.0). Every component of the MCP ecosystem hardened in one day. Full technical recap: MCP security sprint delivered: v1.9.0, 10 chantiers, hardened ecosystem.

This page stays published as an archive — to show the trajectory of an announced sprint, then kept. All original content below is preserved.

Original status (pre-delivery)

This page publicly documented an ongoing hardening sprint on arleo.eu’s MCP infrastructure. For security reasons, specific details of each chantier were not exposed until fixes were delivered (“sec-first” philosophy: don’t publish an attack roadmap).

Why this transparency

I debated whether to publish this page. Arguments for transparency:

• Public commitment = healthy pressure on yourself to deliver
• Documentation of a homelab whose goal is to learn and share
• Honesty with readers consuming other technical articles

Arguments against:

• Attack roadmap: if I precisely list what’s not yet protected, I give clues to a patient attacker
• Artificial pressure: announcing a sprint then not delivering = worse than announcing nothing

Adopted compromise: publish the direction and hardening domains without specifying what’s weak today. Specific technical detail published on delivery.

Sprint scope

The sprint covered 10 chantiers grouped into 4 domains:

1. Application hardening (FastAPI + Pydantic)

Reinforcement of MCP entry layers: strict input validation, unified error handling, no information leak in responses (stack traces, internal paths, lib versions).

2. Authentication and tokens

Refactor of MCP access token management: lifetime, rotation, revocation, hashing in storage. Allow cutting off a compromised client’s access without redeploying the service.

3. Observability and audit

Integration of JSON structured logs ingested in BetterStack via Vector. Each MCP call must produce a traceable event: who, what, when, duration, status. Enables anomaly detection in near real-time.

4. Infrastructure and resilience

TLS for internal traffic between NUC and VM, dedicated ModSec rules on the /mcp path, disaster recovery runbook (token theft, server compromise, data loss).

What was already in place before the sprint

To not create false impressions, here are the layers already in place on infrastructure before the sprint (so out of scope):

• nginx + mandatory TLS 1.3 (Mozilla Modern config)
• Cloudflare WAF + Bot Management + IP whitelist
• ModSecurity + OWASP CRS 4.x on all vhosts
• CrowdSec in WAF mode + Cloudflare bouncer
• systemd hardening at level 1.7 (cf. systemd hardening)
• HMAC validation on webhooks
• Frontmatter Pydantic validation (1 chantier of 4 in the validation category)

The sprint aimed to complete this base, not replace it.

Method

For each chantier:

1. Implemented locally + unit tests
2. Validated on mcp-test-vm (pre-prod VM)
3. Deployed to prod only after passing tests
4. Structured JSON audit log for deployment traceability
5. Post-mortem or technical write-up published after delivery

No direct prod deployment without pre-prod step.

Published releases

3 coordinated releases planned, all delivered the same day:

See the victory recap for details.

All commits are GPG-signed, fingerprint 33133FBFAFFFCA48AFFD3953E34BC7955D46431A:

• github.com/jmrGrav/hugo-mcp v1.9.0
• github.com/jmrGrav/mcp-oauth-proxy v2.1.0
• github.com/jmrGrav/mcp-installer v1.3.0

ETA (historical)

Started May 9, 2026. Planned ETA: late May 2026.

Actual: full delivery on May 9, 2026 same day, in a marathon session.

Why now

Several converging triggers:

• Internal audit of v1.6.0/v1.7.0/v1.8.1 code identified specific gaps (without going into details here)
• Several benign incidents highlighted operational blind spots (cf. MCP timeouts post-mortem, Cloudflare Bot Mgmt post-mortem)
• The Webhook Git Strategy 4 project (cf. webhook git roadmap) needs several sprint primitives (rate limiting, audit logs, strict validation) before being implemented

Aligning security chantiers with short-term need = good ROI.

Commitment kept

The compromise announced before the sprint (sec-first, transparency on direction, details on delivery) was kept. No specific information about pre-sprint vulnerabilities was published until fixes were in prod. Full recap: MCP security sprint delivered.