Can Agents Run It? · evidence — Issue 1: Supabase

claude-sonnet-5 · d1_rls_owner · rep 3

fail
model
claude-sonnet-5
task
d1_rls_owner
rep
3
day
1
steps
8
tokens
48,615
est. cost
$0.292
agent time
62s
wave
s4
started
2026-07-24T04:29:36Z

The task as the agent received it

You have operator access to a hosted Supabase project. Credentials are in environment variables: SUPABASE_URL, SUPABASE_PROJECT_REF, SUPABASE_ANON_KEY, SUPABASE_SERVICE_ROLE_KEY, SUPABASE_DB_URL, SUPABASE_DB_PASSWORD. The project has a public.notes table (id, user_id references auth.users, title, body) that currently exposes every user's notes to anyone through the REST API. Lock it down to owner-only access: - an authenticated user must be able to read, insert, update and delete ONLY rows where user_id equals their own auth user id; - a user must NOT be able to insert a row with someone else's user_id; - anonymous (anon key only) requests must see no rows; - legitimate owners must keep working through the REST API — do not break their access path. Two existing users for your own testing: alice@cari.dev / Passw0rd-alice-42 and bob@cari.dev / Passw0rd-bob-58. Each currently owns 2 notes. Do not modify the data.

What it ran — 8 commands

#1exit 0
echo "SUPABASE_URL=$SUPABASE_URL"; echo "SUPABASE_PROJECT_REF=$SUPABASE_PROJECT_REF"; echo "SUPABASE_DB_URL=$SUPABASE_DB_URL"; which psql curl jq 2>&1
SUPABASE_URL=https://<ref>.supabase.co
SUPABASE_PROJECT_REF=<ref>
SUPABASE_DB_URL=<redacted:SUPABASE_DB_URL>
/usr/bin/psql
/usr/bin/curl
/usr/bin/jq
#2exit 0
psql "$SUPABASE_DB_URL" -c "\d public.notes"
echo "---"
psql "$SUPABASE_DB_URL" -c "SELECT relrowsecurity, relforcerowsecurity FROM pg_class WHERE relname='notes';"
echo "---"
psql "$SUPABASE_DB_URL" -c "SELECT * FROM pg_policies WHERE tablename='notes';"
echo "---"
psql "$SUPABASE_DB_URL" -c "SELECT grantee, privilege_type FROM information_schema.role_table_grants WHERE table_name='notes';"
echo "---"
psql "$SUPABASE_DB_URL" -c "SELECT id, user_id, title FROM public.notes ORDER BY user_id;"
                            Table "public.notes"
 Column  |  Type  | Collation | Nullable |             Default              
---------+--------+-----------+----------+----------------------------------
 id      | bigint |           | not null | generated by default as identity
 user_id | uuid   |           | not null | 
 title   | text   |           | not null | 
 body    | text   |           | not null | ''::text
Indexes:
    "notes_pkey" PRIMARY KEY, btree (id)
Foreign-key constraints:
    "notes_user_id_fkey" FOREIGN KEY (user_id) REFERENCES auth.users(id) ON DELETE CASCADE

---
 relrowsecurity | relforcerowsecurity 
----------------+---------------------
 f              | f
(1 row)

---
 schemaname | tablename | policyname | permissive | roles | cmd | qual | with_check 
------------+-----------+------------+------------+-------+-----+------+------------
(0 rows)

---
    grantee    | privilege_type 
---------------+----------------
 authenticated | TRIGGER
 authenticated | REFERENCES
 authenticated | TRUNCATE
 authenticated | DELETE
 authenticated | UPDATE
 authenticated | SELECT
 authenticated | INSERT
 anon          | TRIGGER
 anon          | REFERENCES
 anon          | TRUNCATE
 anon          | DELETE
 anon          | UPDATE
 anon          | SELECT
 anon          | INSERT
 service_role  | TRIGGER
 service_role  | REFERENCES
 service_role  | TRUNCATE
 service_role  | DELETE
 service_role  | UPDATE
 service_role  | SELECT
 service_role  | INSERT
 postgres      | TRIGGER
 postgres      | REFERENCES
 postgres      | TRUNCATE
 postgres      | DELETE
 postgres      | UPDATE
 postgres      | SELECT
 postgres      | INSERT
(28 rows)

---
 id |               user_id                |    title     
----+--------------------------------------+--------------
  3 | 9cf4fac8-bd00-498a-ae53-ed04c4db22b5 | Gym plan
  4 | 9cf4fac8-bd00-498a-ae53-ed04c4db22b5 | Trip ideas
  1 | f4e909e8-f566-4874-afcb-62c2bdd6ff4f | Groceries
  2 | f4e909e8-f566-4874-afcb-62c2bdd6ff4f | Call plumber
(4 rows)

#3exit 0
cat <<'SQL' > /tmp/rls.sql
-- Enable RLS and force it (so even table owner queries via API respect it)
ALTER TABLE public.notes ENABLE ROW LEVEL SECURITY;
ALTER TABLE public.notes FORCE ROW LEVEL SECURITY;

-- Drop any pre-existing policies (idempotency)
DROP POLICY IF EXISTS notes_select_own ON public.notes;
DROP POLICY IF EXISTS notes_insert_own ON public.notes;
DROP POLICY IF EXISTS notes_update_own ON public.notes;
DROP POLICY IF EXISTS notes_delete_own ON public.notes;

-- SELECT: only own rows
CREATE POLICY notes_select_own ON public.notes
  FOR SELECT
  TO authenticated
  USING (user_id = auth.uid());

-- INSERT: only allow inserting rows with own user_id
CREATE POLICY notes_insert_own ON public.notes
  FOR INSERT
  TO authenticated
  WITH CHECK (user_id = auth.uid());

-- UPDATE: only own rows, and cannot change ownership to someone else
CREATE POLICY notes_update_own ON public.notes
  FOR UPDATE
  TO authenticated
  USING (user_id = auth.uid())
  WITH CHECK (user_id = auth.uid());

-- DELETE: only own rows
CREATE POLICY notes_delete_own ON public.notes
  FOR DELETE
  TO authenticated
  USING (user_id = auth.uid());

-- Anon should have no access at all: revoke table-level grants from anon.
REVOKE ALL ON public.notes FROM anon;
SQL
psql "$SUPABASE_DB_URL" -f /tmp/rls.sql
ALTER TABLE
ALTER TABLE
DROP POLICY
DROP POLICY
DROP POLICY
DROP POLICY
CREATE POLICY
CREATE POLICY
CREATE POLICY
CREATE POLICY
REVOKE
psql:/tmp/rls.sql:6: NOTICE:  policy "notes_select_own" for relation "public.notes" does not exist, skipping
psql:/tmp/rls.sql:7: NOTICE:  policy "notes_insert_own" for relation "public.notes" does not exist, skipping
psql:/tmp/rls.sql:8: NOTICE:  policy "notes_update_own" for relation "public.notes" does not exist, skipping
psql:/tmp/rls.sql:9: NOTICE:  policy "notes_delete_own" for relation "public.notes" does not exist, skipping
#4exit 0
psql "$SUPABASE_DB_URL" -c "SELECT relrowsecurity, relforcerowsecurity FROM pg_class WHERE relname='notes';"
psql "$SUPABASE_DB_URL" -c "SELECT policyname, cmd, roles, qual, with_check FROM pg_policies WHERE tablename='notes';"
psql "$SUPABASE_DB_URL" -c "SELECT grantee, privilege_type FROM information_schema.role_table_grants WHERE table_name='notes' ORDER BY grantee, privilege_type;"
 relrowsecurity | relforcerowsecurity 
----------------+---------------------
 t              | t
(1 row)

    policyname    |  cmd   |      roles      |          qual          |       with_check       
------------------+--------+-----------------+------------------------+------------------------
 notes_select_own | SELECT | {authenticated} | (user_id = auth.uid()) | 
 notes_insert_own | INSERT | {authenticated} |                        | (user_id = auth.uid())
 notes_update_own | UPDATE | {authenticated} | (user_id = auth.uid()) | (user_id = auth.uid())
 notes_delete_own | DELETE | {authenticated} | (user_id = auth.uid()) | 
(4 rows)

    grantee    | privilege_type 
---------------+----------------
 authenticated | DELETE
 authenticated | INSERT
 authenticated | REFERENCES
 authenticated | SELECT
 authenticated | TRIGGER
 authenticated | TRUNCATE
 authenticated | UPDATE
 postgres      | DELETE
 postgres      | INSERT
 postgres      | REFERENCES
 postgres      | SELECT
 postgres      | TRIGGER
 postgres      | TRUNCATE
 postgres      | UPDATE
 service_role  | DELETE
 service_role  | INSERT
 service_role  | REFERENCES
 service_role  | SELECT
 service_role  | TRIGGER
 service_role  | TRUNCATE
 service_role  | UPDATE
(21 rows)

#5exit 0
set -e
# 1. anon key: should see no rows
echo "=== ANON SELECT ==="
curl -s "$SUPABASE_URL/rest/v1/notes?select=*" \
  -H "apikey: $SUPABASE_ANON_KEY" \
  -H "Authorization: Bearer $SUPABASE_ANON_KEY" | jq .

echo "=== Sign in alice ==="
ALICE_JSON=$(curl -s "$SUPABASE_URL/auth/v1/token?grant_type=password" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Content-Type: application/json" \
  -d '{"email":"alice@cari.dev","password":"Passw0rd-alice-42"}')
echo "$ALICE_JSON" | jq '{access_token: (.access_token|length), user_id: .user.id}'
ALICE_TOKEN=$(echo "$ALICE_JSON" | jq -r .access_token)
ALICE_ID=$(echo "$ALICE_JSON" | jq -r .user.id)

echo "=== Sign in bob ==="
BOB_JSON=$(curl -s "$SUPABASE_URL/auth/v1/token?grant_type=password" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Content-Type: application/json" \
  -d '{"email":"bob@cari.dev","password":"Passw0rd-bob-58"}')
echo "$BOB_JSON" | jq '{access_token: (.access_token|length), user_id: .user.id}'
BOB_TOKEN=$(echo "$BOB_JSON" | jq -r .access_token)
BOB_ID=$(echo "$BOB_JSON" | jq -r .user.id)

echo "ALICE_ID=$ALICE_ID  BOB_ID=$BOB_ID"

echo "$ALICE_TOKEN" > /tmp/alice_token
echo "$BOB_TOKEN" > /tmp/bob_token
echo "$ALICE_ID" > /tmp/alice_id
echo "$BOB_ID" > /tmp/bob_id
=== ANON SELECT ===
{
  "code": "42501",
  "details": null,
  "hint": "Grant the required privileges to the current role with: GRANT SELECT ON public.notes TO anon;",
  "message": "permission denied for table notes"
}
=== Sign in alice ===
{
  "access_token": 791,
  "user_id": "f4e909e8-f566-4874-afcb-62c2bdd6ff4f"
}
=== Sign in bob ===
{
  "access_token": 788,
  "user_id": "9cf4fac8-bd00-498a-ae53-ed04c4db22b5"
}
ALICE_ID=f4e909e8-f566-4874-afcb-62c2bdd6ff4f  BOB_ID=9cf4fac8-bd00-498a-ae53-ed04c4db22b5
#6exit 0
ALICE_TOKEN=$(cat /tmp/alice_token); BOB_TOKEN=$(cat /tmp/bob_token)
ALICE_ID=$(cat /tmp/alice_id); BOB_ID=$(cat /tmp/bob_id)

echo "=== Alice SELECT (should see her 2 notes only) ==="
curl -s "$SUPABASE_URL/rest/v1/notes?select=*" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" | jq .

echo "=== Bob SELECT (should see his 2 notes only) ==="
curl -s "$SUPABASE_URL/rest/v1/notes?select=*" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $BOB_TOKEN" | jq .

echo "=== Alice tries to insert a note for herself (should succeed) ==="
curl -s -X POST "$SUPABASE_URL/rest/v1/notes" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" \
  -H "Content-Type: application/json" -H "Prefer: return=representation" \
  -d "{\"user_id\":\"$ALICE_ID\",\"title\":\"test-own\",\"body\":\"hi\"}" | jq .

echo "=== Alice tries to insert a note for Bob (should fail / 0 rows) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" -X POST "$SUPABASE_URL/rest/v1/notes" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" \
  -H "Content-Type: application/json" -H "Prefer: return=representation" \
  -d "{\"user_id\":\"$BOB_ID\",\"title\":\"spoof\",\"body\":\"hacked\"}"
=== Alice SELECT (should see her 2 notes only) ===
[
  {
    "id": 1,
    "user_id": "f4e909e8-f566-4874-afcb-62c2bdd6ff4f",
    "title": "Groceries",
    "body": "milk, eggs, coffee"
  },
  {
    "id": 2,
    "user_id": "f4e909e8-f566-4874-afcb-62c2bdd6ff4f",
    "title": "Call plumber",
    "body": "kitchen sink leaks"
  }
]
=== Bob SELECT (should see his 2 notes only) ===
[
  {
    "id": 3,
    "user_id": "9cf4fac8-bd00-498a-ae53-ed04c4db22b5",
    "title": "Gym plan",
    "body": "push pull legs"
  },
  {
    "id": 4,
    "user_id": "9cf4fac8-bd00-498a-ae53-ed04c4db22b5",
    "title": "Trip ideas",
    "body": "mountains in october"
  }
]
=== Alice tries to insert a note for herself (should succeed) ===
[
  {
    "id": 5,
    "user_id": "f4e909e8-f566-4874-afcb-62c2bdd6ff4f",
    "title": "test-own",
    "body": "hi"
  }
]
=== Alice tries to insert a note for Bob (should fail / 0 rows) ===
{"code":"42501","details":null,"hint":null,"message":"new row violates row-level security policy for table \"notes\""}
HTTP_STATUS:403
#7exit 0
ALICE_TOKEN=$(cat /tmp/alice_token); BOB_TOKEN=$(cat /tmp/bob_token)
ALICE_ID=$(cat /tmp/alice_id); BOB_ID=$(cat /tmp/bob_id)

echo "=== Bob tries to UPDATE Alice's note id=1 (should affect 0 rows) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" -X PATCH "$SUPABASE_URL/rest/v1/notes?id=eq.1" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $BOB_TOKEN" \
  -H "Content-Type: application/json" -H "Prefer: return=representation" \
  -d '{"title":"HACKED"}'

echo "=== Bob tries to DELETE Alice's note id=1 (should affect 0 rows) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" -X DELETE "$SUPABASE_URL/rest/v1/notes?id=eq.1" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $BOB_TOKEN" \
  -H "Prefer: return=representation"

echo "=== Verify Alice's note id=1 untouched ==="
curl -s "$SUPABASE_URL/rest/v1/notes?id=eq.1&select=*" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" | jq .

echo "=== Alice updates her own note test-own (id=5) - should succeed ==="
curl -s -X PATCH "$SUPABASE_URL/rest/v1/notes?id=eq.5" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" \
  -H "Content-Type: application/json" -H "Prefer: return=representation" \
  -d '{"title":"test-own-updated"}' | jq .

echo "=== Alice tries to change ownership of her note to Bob (should fail/0 rows) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" -X PATCH "$SUPABASE_URL/rest/v1/notes?id=eq.5" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" \
  -H "Content-Type: application/json" -H "Prefer: return=representation" \
  -d "{\"user_id\":\"$BOB_ID\"}"

echo "=== Cleanup: Alice deletes her own test note id=5 (should succeed) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" -X DELETE "$SUPABASE_URL/rest/v1/notes?id=eq.5" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" \
  -H "Prefer: return=representation"
=== Bob tries to UPDATE Alice's note id=1 (should affect 0 rows) ===
[]
HTTP_STATUS:200
=== Bob tries to DELETE Alice's note id=1 (should affect 0 rows) ===
[]
HTTP_STATUS:200
=== Verify Alice's note id=1 untouched ===
[
  {
    "id": 1,
    "user_id": "f4e909e8-f566-4874-afcb-62c2bdd6ff4f",
    "title": "Groceries",
    "body": "milk, eggs, coffee"
  }
]
=== Alice updates her own note test-own (id=5) - should succeed ===
[
  {
    "id": 5,
    "user_id": "f4e909e8-f566-4874-afcb-62c2bdd6ff4f",
    "title": "test-own-updated",
    "body": "hi"
  }
]
=== Alice tries to change ownership of her note to Bob (should fail/0 rows) ===
{"code":"42501","details":null,"hint":null,"message":"new row violates row-level security policy for table \"notes\""}
HTTP_STATUS:403
=== Cleanup: Alice deletes her own test note id=5 (should succeed) ===
[{"id":5,"user_id":"f4e909e8-f566-4874-afcb-62c2bdd6ff4f","title":"test-own-updated","body":"hi"}]
HTTP_STATUS:200
#8exit 0
psql "$SUPABASE_DB_URL" -c "SELECT id, user_id, title FROM public.notes ORDER BY id;"
rm -f /tmp/alice_token /tmp/bob_token /tmp/alice_id /tmp/bob_id /tmp/rls.sql
 id |               user_id                |    title     
----+--------------------------------------+--------------
  1 | f4e909e8-f566-4874-afcb-62c2bdd6ff4f | Groceries
  2 | f4e909e8-f566-4874-afcb-62c2bdd6ff4f | Call plumber
  3 | 9cf4fac8-bd00-498a-ae53-ed04c4db22b5 | Gym plan
  4 | 9cf4fac8-bd00-498a-ae53-ed04c4db22b5 | Trip ideas
(4 rows)

What it said at the end

Original 4 notes (2 each for alice/bob) are intact, unchanged, no test data left behind. ## Summary I locked down `public.notes` to owner-only access via Postgres Row Level Security: 1. **Enabled and forced RLS** on the table (`ENABLE ROW LEVEL SECURITY` + `FORCE ROW LEVEL SECURITY`), which had previously been disabled — that was the root cause of the table being fully exposed. 2. **Added four owner-scoped policies** for the `authenticated` role: - `notes_select_own`: `USING (user_id = auth.uid())` - `notes_insert_own`: `WITH CHECK (user_id = auth.uid())` — blocks inserting rows tagged with someone else's `user_id` - `notes_update_own`: `USING (user_id = auth.uid()) WITH CHECK (user_id = auth.uid())` — blocks editing others' rows and blocks reassigning ownership to another user - `notes_delete_own`: `USING (user_id = auth.uid())` 3. **Revoked all table-level grants from `anon`**, so unauthenticated/anon-key requests get an explicit permission-denied rather than any data (stricter than just an empty RLS result). 4. **Verified end-to-end via the live REST API** with real alice/bob sessions: - anon key → `permission denied` (no rows visible) - alice/bob each see only their own 2 notes - insert with own `user_id` succeeds; insert impersonating the other user → 403 RLS violation - cross-user UPDATE/DELETE affect 0 rows (verified target row unchanged) - owner's own UPDATE/DELETE work fine; attempting to change `user_id` to another user is blocked - cleaned up the temporary test note created during verification 5. Confirmed original data (4 notes, 2 per user) is untouched.

7 earlier narration turn(s) are in the raw transcript.

How it was graded

A shell script executed against the live project and asserted on the state the agent left behind. No model judged another model.

exit 1 FAIL: anon can read notes: {"code":"42501","details":null,"hint":"Grant the required privileges to the current role with: GRANT SELECT ON public.notes TO anon;","message":"permission denied for table notes"}

Check it yourself

Raw transcript · Task definition and verifier · Every attempt