Remix V2 Meta Sessions Review

Security

Reviews Remix v2 code for v1-shape meta exports (BREAKING in v2), cookie security gaps (httpOnly, secure, secrets rotation), auth gates in wrong layer, and missing CSRF. Use when reviewing meta/SEO, session, auth, or form-mutation code in a Remix v2 codebase.

Install

openclaw skills install remix-v2-meta-sessions-review

Remix v2 Meta, Sessions, Auth, and CSRF Code Review

Reviews Remix v2 meta/SEO, session, auth-gate, and CSRF code paths. Loaded by the umbrella review-remix-v2 reviewer when a diff touches any of: meta/links exports, root.tsx, *.server.ts session/cookie modules, loaders/actions reading or writing session, or <Form>/useFetcher mutations.

See beagle-remix-v2:remix-v2-meta-sessions for canonical patterns.

Quick Reference

Issue TypeReference
meta returning v1 object shape (BREAKING), OG shorthand, document.title in effect, missing <Meta />/<Links />, parent mergereferences/meta-v2-shape.md
Missing httpOnly/secure, hardcoded secrets, single-string secrets, replace-not-prepend rotationreferences/cookie-security.md
Auth check in component, logout in loader, missing commitSession, flash without commitreferences/auth-gates.md
Manual fetch POST bypassing CSRF, token in session cookie, no CSRF protection, shared secretsreferences/csrf.md

Highest-stakes detection — call out first: v1 meta object shape (return { title, description }) in a v2 codebase. It typechecks, but the runtime ignores it and the page renders with no title and no meta tags. Grep every export const meta and confirm the return value starts with [, not {.

Review Checklist

  • meta returns MetaDescriptor[] (array starts with [), NOT the v1 object shape
  • OG / Twitter tags use { property, content }, NOT v1 shorthand { "og:title": "..." }
  • No document.title = "..." or useEffect(() => { document.title = ... }) — meta is set via the meta export
  • root.tsx includes <Meta /> and <Links /> inside <head>
  • Child meta that wants parent values uses matches.flatMap((m) => m.meta ?? [])
  • meta null-guards data (loader may not have run / returned undefined on 404)
  • Cookie config sets httpOnly: true and secure: process.env.NODE_ENV === "production"
  • secrets is read from process.env (no hardcoded strings, no committed .env.example values)
  • secrets is an array supporting rotation (prepend new, keep old) — not a single value
  • Every session.set/session.unset/session.flash is followed by a response with "Set-Cookie": await commitSession(session)
  • Auth gate is in loader (or action) via requireUserId(request) — NOT a component-level redirect
  • Logout is an action (POST), not a loader (GET)
  • Mutating actions call csrf.validate(request) when CSRF protection is in use
  • CSRF token uses a dedicated createCookie("csrf", ...), NOT the session cookie
  • Mutations use <Form> / useFetcher so AuthenticityTokenInput attaches the token (no manual fetch POST)

Valid Patterns (Do NOT Flag)

These are correct usage — do not report as issues:

  • sameSite: "lax" — acceptable default. Not every app needs "strict"; flag only when threat model warrants stricter (e.g. CSRF protection is otherwise absent).
  • meta returning [] — legitimate when the route intentionally emits no meta (inherits root tags or relies on a sibling).
  • links returning [] — legitimate when the route has no route-specific stylesheets or preloads.
  • session.flash(...) followed on the next line by commitSession(session) — the standard 2-line flash pattern. The separation is correct; do not flag it as "missing commit".
  • Auth check in action (not loader) — correct for POST-only routes (e.g. logout, delete). Loaders gate GETs; actions gate mutations.
  • charset and viewport as plain JSX <meta> in root.tsx's <head> — preferred over the meta export to avoid duplicate-tag warnings under v2's no-merge behavior.
  • secrets: [process.env.X!, process.env.X_OLD!]! non-null assertion is acceptable when a fail-fast guard above (if (!process.env.X) throw) is present.
  • throw redirect(...) inside a loader/action — canonical Remix pattern; the thrown response is intentional.
  • commitSession called in a loader (not just an action) — required when a loader reads a flash message and must clear it.

Context-Sensitive Rules

Only flag these issues when the specific context applies:

IssueFlag ONLY IF
Missing CSRF validation in actionApp declares remix-utils/csrf as its protection mechanism, OR the action is public-facing (not internal/VPN-gated) AND no Origin check is present
sameSite: "lax"App has no library-based CSRF protection AND no Origin check — "lax" then becomes the only defense and is insufficient
Missing secure flagCookie config is the production session/CSRF cookie (not a test fixture or commented example)
meta returning []The route is documented as needing route-specific tags (e.g. a public landing page) — empty is usually intentional inheritance, do not flag by default
Auth check in action not loaderRoute is GET-renderable (has a loader) — for POST-only routes, action is the correct gate
Logout in action AND <Form method="post">Never flag — that is the canonical pattern
Manual fetch POSTThe target is an internal Remix action AND no CSRF token is attached via headers
secrets: [singleValue]App is in production OR has been deployed for long enough to need rotation — flag as recommendation, not CRITICAL

Hard gates (before writing findings)

Run these in order. Do not draft user-facing findings until every gate passes for the batch you are about to report.

  1. Location evidencePass: Each issue lists a repo path and either a line range or a short verbatim quote from the file you read. Diff-only or memory-based claims do not pass. For meta/links/session issues, the cited file is a .ts/.tsx route module, root.tsx, or *.server.ts — not a generic config file.

  2. Exemption checkPass: For each issue, you can state in one line why it is not covered by Valid Patterns (Do NOT Flag). In particular: sameSite: "lax", empty meta/links arrays, and the standard flash + commitSession two-line pattern must be explicitly cleared.

  3. Meta-shape checkPass: Before flagging anything about meta, you read the actual function body and confirmed what it returns. TypeScript may have masked the shape (a v1 object can satisfy a poorly-typed MetaFunction alias). The check is: the return expression starts with [ and every element is a descriptor object. If it starts with {, that is the v1 shape — flag as CRITICAL. If it is [], that is valid (do not flag).

  4. ProtocolPass: You completed the Pre-Report Verification Checklist in review-verification-protocol for this review.

When to Load References

  • Reviewing any export const meta or export const links, or root.tsxmeta-v2-shape.md
  • Reviewing createCookieSessionStorage, createCookie, or any *.server.ts that configures cookies → cookie-security.md
  • Reviewing loaders/actions that read or write session, or any auth helper → auth-gates.md
  • Reviewing forms, fetchers, or any mutating route → csrf.md

Review Questions

  1. Does every meta export return an array, and is every OG/Twitter tag { property, content }?
  2. Does root.tsx include <Meta /> and <Links /> inside <head>?
  3. Are cookies httpOnly + secure: NODE_ENV === 'production' with secrets from env in an array (rotation-ready)?
  4. Is every session mutation followed by a Set-Cookie: await commitSession(session) header?
  5. Is auth gated in the loader/action via a throwing helper, never in a component?
  6. Is logout an action (POST), and do mutating actions validate CSRF (or document the threat model)?

Additional Documentation

Before Submitting Findings

Complete Hard gates (especially gate 3 — meta-shape check), then report only issues that still pass the review-verification-protocol pre-report checks.