cd /news/ai-tools/show-hn-rlsgate-block-the-supabase-r… · home topics ai-tools article
[ARTICLE · art-35210] src=github.com ↗ pub= topic=ai-tools verified=true sentiment=↑ positive

Show HN: Rlsgate – Block the Supabase RLS leak before you deploy (CLI)

Rlsgate, a new open-source CLI tool, blocks Supabase Row Level Security leaks before deployment by scanning local migrations, policies, and env files for critical vulnerabilities like the CVE-2025-48757 class that exposed 170+ apps. The tool runs as a local-first static scanner with no database connection or telemetry, and integrates as a CLI, Claude Code skill, or GitHub Action to catch holes before they reach production.

read4 min views1 publishedJun 21, 2026
Show HN: Rlsgate – Block the Supabase RLS leak before you deploy (CLI)
Image: source

The Supabase deploy-gate that runs where you vibe-code — and blocks only on the holes that are truly dangerous.

In 2026, a wave of AI-built ("vibe-coded") apps shipped to production with the same handful of security holes. CVE-2025-48757 and the Lovable disclosure cataloged 170+ live apps leaking user PII — most through one anti-pattern: a Row Level Security policy that lets any logged-in user read everyone's rows. Studies of vibe-coded apps found ~80% repeat the same RLS mistake and ~72% ship a hardcoded secret somewhere.

rlsgate

is a local-first, static scanner that reads your Supabase migrations, RLS policies, env files, and frontend bundle and blocks the deploy when it finds the finite set of high-signal holes that actually leak. No database connection, no telemetry, no account. It runs in seconds, as a CLI, a Claude Code skill, or a GitHub Action.

$ rlsgate scan
rlsgate  ·  1 migrations, 1 env, 2 source files scanned

✖ CRITICAL  Table public.profiles holds personal data but Row Level Security is never enabled
    where: supabase/migrations/0001_init.sql:2
    why:   With RLS off in a client-reachable schema, anyone holding the public anon key can read every row.
    fix:   ALTER TABLE public.profiles ENABLE ROW LEVEL SECURITY; then add an ownership policy.

✖ CRITICAL  RLS policy 'read all posts' grants every authenticated user access to public.posts
    where: supabase/migrations/0001_init.sql:15
    fix:   Bind the policy to the row owner, e.g. USING (auth.uid() = user_id).

▲ HIGH      Webhook handler does not verify the request signature (app/api/stripe/webhook/route.ts)
    ...
  3 critical  2 high
$ echo $?
1

Plenty of tools scan vibe-coded apps. rlsgate

is the one that is local-first, runs inside your build loop, and blocks at deploy — not a dashboard you visit, not a sidecar you run in production.

vs hosted SaaS scanners— they guess at your security fromoutsideyour live URL and want a token to your repo.rlsgate

reads your actual migrations and RLS policies locally. No DB connection, no account, no token handoff, no telemetry.vs runtime sidecars / firewalls— they filter requestsafterdeploy, in front of your app.rlsgate

catches the holebeforedeploy, in your repo, where it's a one-line fix instead of an incident.vs broad scanners— they compete on rule count (hundreds to thousands), which means noise, which means you turn them off.rlsgate

ships a finite, high-precision set of checks for the holes that actually leak — including the CVE-2025-48757 "any authenticated user can read any row" class that breadth scanners miss — so it's a gate you'll actually leave on.

It's the same checks across three surfaces with full parity: a CLI, a Claude Code skill that fires mid-build (inside the AI tool generating your app), and a GitHub Action that blocks the merge. Works across any builder — Lovable, Bolt, Cursor, v0, or hand-rolled.

pip install rlsgate         # or: uv tool install rlsgate
rlsgate scan                # scan the current directory

No Python project? A zero-install run:

uvx rlsgate scan ./my-app
rlsgate scan [PATH]              # scan a project (default: .)
rlsgate scan --json             # machine-readable output
rlsgate scan --fail-on critical # only CRITICAL fails the gate (default: high)
rlsgate scan --ai               # add AI-drafted fix snippets (needs ANTHROPIC_API_KEY)
rlsgate rules                   # list the checks

Exit codes: 0

clean (or only findings below --fail-on

) · 1

blocking findings · 2

usage error. The non-zero exit is what makes it a gate.

Rule Severity The hole
rls-authenticated
CRITICAL RLS policy authorizes any authenticated user instead of the row owner — the CVE-2025-48757 class
rls-disabled
CRITICAL/HIGH A user/PII table created without ENABLE ROW LEVEL SECURITY (wide open to the anon key)
anon-access
CRITICAL/HIGH Data reachable by the unauthenticated anon role via a permissive policy or grant
public-bucket
HIGH A Supabase Storage bucket created public (every object served to anyone with the URL)
exposed-secret
CRITICAL/HIGH A real secret committed to .env , or a service-role key / sk- key shipped to the browser bundle
unverified-webhook
HIGH A webhook endpoint that acts on the body without verifying the provider's signature

The Supabase anon key (a public JWT with role: anon

) is intentionally public and is never flagged — only the dangerous service_role

key is.

name: rlsgate
on: [pull_request]
jobs:
  scan:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: GerardoRdz96/rlsgate@v0.1.0
        with:
          path: .
          fail-on: high

Copy skill/

into your project's .claude/skills/rlsgate/

(or install the repo as a plugin). Then, in the agent loop before deploy:

/rlsgate

The skill runs the gate and brings the findings into the conversation so the agent fixes them before shipping.

Not a full security audit. It checks a finite, high-signal ruleset, statically. It will not catch logic bugs, business-rule auth flaws, or holes that only appear at runtime.Not a database scanner. v1 reads files only — it never connects to your Supabase project. A policy thatlookscorrect but behaves differently at runtime is out of scope.Not an auto-fixer. The deterministic finding is the source of truth. The optional--ai

fix is clearly labeled AI-drafted and must be reviewed before you apply it.

A clean rlsgate

run means "none of the known high-signal holes are present," not "this app is secure."

MIT © 2026 Penguin Alley

── more in #ai-tools 4 stories · sorted by recency
── more on @supabase 3 stories trending now
sponsored brought to you by zahid.host 4,200+ EU-deployed projects
reading about agents? ship yours in a single git push.

Run your AI side-project on zahid.host

EU-based hosting, git-push deploys, automatic HTTPS, no cold starts. Free tier with a custom domain — perfect for shipping the agent you just read about.

$git push zahid main
Live at https://your-agent.zahid.host
Get free account → Pricing
from €0/mo · no card required
LIVE [news/show-hn-rlsgate-bloc…] indexed:0 read:4min 2026-06-21 ·