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

claude-sonnet-5 · d1_rls_owner · rep 2

pass
model
claude-sonnet-5
task
d1_rls_owner
rep
2
day
1
steps
10
tokens
58,515
est. cost
$0.351
agent time
70s
wave
s4
started
2026-07-24T04:28:10Z

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 — 10 commands

#1exit 0
echo "SUPABASE_URL: $SUPABASE_URL"; echo "SUPABASE_PROJECT_REF: $SUPABASE_PROJECT_REF"; echo "DB URL set: $([ -n "$SUPABASE_DB_URL" ] && echo yes || echo no)"; which psql curl jq 2>&1
SUPABASE_URL: https://<ref>.supabase.co
SUPABASE_PROJECT_REF: <ref>
DB URL set: yes
/usr/bin/psql
/usr/bin/curl
/usr/bin/jq
#2exit 0
psql "$SUPABASE_DB_URL" -c "\d public.notes" 2>&1
echo "----"
psql "$SUPABASE_DB_URL" -c "select relname, relrowsecurity, relforcerowsecurity from pg_class where relname='notes';" 2>&1
echo "----"
psql "$SUPABASE_DB_URL" -c "select * from pg_policies where tablename='notes';" 2>&1
echo "----"
psql "$SUPABASE_DB_URL" -c "select id, user_id, title from public.notes order by user_id;" 2>&1
                            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

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

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

----
 id |               user_id                |    title     
----+--------------------------------------+--------------
  1 | 0c3dd2dd-39fb-4167-82d5-8977bee1a21f | Groceries
  2 | 0c3dd2dd-39fb-4167-82d5-8977bee1a21f | Call plumber
  3 | bf88dbef-e3e9-4ca9-b6ab-5e30dbcc3a3f | Gym plan
  4 | bf88dbef-e3e9-4ca9-b6ab-5e30dbcc3a3f | Trip ideas
(4 rows)

#3exit 0
psql "$SUPABASE_DB_URL" -c "select grantee, privilege_type from information_schema.role_table_grants where table_name='notes';" 2>&1
echo "----"
psql "$SUPABASE_DB_URL" -c "select rolname from pg_roles where rolname in ('anon','authenticated','service_role');" 2>&1
    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)

----
    rolname    
---------------
 authenticated
 anon
 service_role
(3 rows)

#4exit 0
cat <<'SQL' > /tmp/rls_notes.sql
-- Enable RLS (and force it so even table owner is constrained, defense in depth)
ALTER TABLE public.notes ENABLE ROW LEVEL SECURITY;
ALTER TABLE public.notes FORCE ROW LEVEL SECURITY;

-- Drop any pre-existing policies with these names, in case of re-run
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: owner only
CREATE POLICY notes_select_own
  ON public.notes
  FOR SELECT
  TO authenticated
  USING (auth.uid() = user_id);

-- INSERT: must insert with your own user_id
CREATE POLICY notes_insert_own
  ON public.notes
  FOR INSERT
  TO authenticated
  WITH CHECK (auth.uid() = user_id);

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

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

-- No policy is created for anon role -> with RLS enabled and no matching
-- permissive policy for anon, anon requests see 0 rows and cannot write.
SQL
psql "$SUPABASE_DB_URL" -f /tmp/rls_notes.sql 2>&1
ALTER TABLE
ALTER TABLE
psql:/tmp/rls_notes.sql:6: NOTICE:  policy "notes_select_own" for relation "public.notes" does not exist, skipping
DROP POLICY
psql:/tmp/rls_notes.sql:7: NOTICE:  policy "notes_insert_own" for relation "public.notes" does not exist, skipping
DROP POLICY
psql:/tmp/rls_notes.sql:8: NOTICE:  policy "notes_update_own" for relation "public.notes" does not exist, skipping
DROP POLICY
psql:/tmp/rls_notes.sql:9: NOTICE:  policy "notes_delete_own" for relation "public.notes" does not exist, skipping
DROP POLICY
CREATE POLICY
CREATE POLICY
CREATE POLICY
CREATE POLICY
#5exit 0
psql "$SUPABASE_DB_URL" -c "select relname, relrowsecurity, relforcerowsecurity from pg_class where relname='notes';" 2>&1
echo "----"
psql "$SUPABASE_DB_URL" -c "select policyname, cmd, roles, qual, with_check from pg_policies where tablename='notes' order by policyname;" 2>&1
 relname | relrowsecurity | relforcerowsecurity 
---------+----------------+---------------------
 notes   | t              | t
(1 row)

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

#6exit 0
set -a
# 1. Anonymous request - should see 0 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 "=== Login 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: .user.id, error}'
ALICE_TOKEN=$(echo "$ALICE_JSON" | jq -r .access_token)
ALICE_ID=$(echo "$ALICE_JSON" | jq -r .user.id)

echo "=== Login 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: .user.id, error}'
BOB_TOKEN=$(echo "$BOB_JSON" | jq -r .access_token)
BOB_ID=$(echo "$BOB_JSON" | jq -r .user.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 ===
[]
=== Login alice ===
{
  "access_token": 791,
  "user": "0c3dd2dd-39fb-4167-82d5-8977bee1a21f",
  "error": null
}
=== Login bob ===
{
  "access_token": 788,
  "user": "bf88dbef-e3e9-4ca9-b6ab-5e30dbcc3a3f",
  "error": null
}
#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 "=== Alice select (should see only her 2 notes) ==="
curl -s "$SUPABASE_URL/rest/v1/notes?select=*" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" | jq .

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

echo "=== Alice tries to select filtering by bob's user_id explicitly (should get empty, not bob's data) ==="
curl -s "$SUPABASE_URL/rest/v1/notes?select=*&user_id=eq.$BOB_ID" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" | jq .
=== Alice select (should see only her 2 notes) ===
[
  {
    "id": 1,
    "user_id": "0c3dd2dd-39fb-4167-82d5-8977bee1a21f",
    "title": "Groceries",
    "body": "milk, eggs, coffee"
  },
  {
    "id": 2,
    "user_id": "0c3dd2dd-39fb-4167-82d5-8977bee1a21f",
    "title": "Call plumber",
    "body": "kitchen sink leaks"
  }
]
=== Bob select (should see only his 2 notes) ===
[
  {
    "id": 3,
    "user_id": "bf88dbef-e3e9-4ca9-b6ab-5e30dbcc3a3f",
    "title": "Gym plan",
    "body": "push pull legs"
  },
  {
    "id": 4,
    "user_id": "bf88dbef-e3e9-4ca9-b6ab-5e30dbcc3a3f",
    "title": "Trip ideas",
    "body": "mountains in october"
  }
]
=== Alice tries to select filtering by bob's user_id explicitly (should get empty, not bob's data) ===
[]
#8exit 0
ALICE_TOKEN=$(cat /tmp/alice_token)
BOB_TOKEN=$(cat /tmp/bob_token)
ALICE_ID=$(cat /tmp/alice_id)
BOB_ID=$(cat /tmp/bob_id)

echo "=== Alice inserts a row with her own user_id (should succeed) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" "$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\":\"owned by alice\"}"

echo ""
echo "=== Alice tries to insert a row claiming bob's user_id (should FAIL) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" "$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\":\"test-impersonate\",\"body\":\"should fail\"}"

echo ""
echo "=== Anon tries to insert a row (should FAIL, no policy for anon) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" "$SUPABASE_URL/rest/v1/notes" \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $SUPABASE_ANON_KEY" \
  -H "Content-Type: application/json" -H "Prefer: return=representation" \
  -d "{\"user_id\":\"$ALICE_ID\",\"title\":\"anon-attempt\",\"body\":\"should fail\"}"
=== Alice inserts a row with her own user_id (should succeed) ===
[{"id":5,"user_id":"0c3dd2dd-39fb-4167-82d5-8977bee1a21f","title":"test-own","body":"owned by alice"}]
HTTP_STATUS:201

=== Alice tries to insert a row claiming bob's user_id (should FAIL) ===
{"code":"42501","details":null,"hint":null,"message":"new row violates row-level security policy for table \"notes\""}
HTTP_STATUS:403

=== Anon tries to insert a row (should FAIL, no policy for anon) ===
{"code":"42501","details":null,"hint":null,"message":"new row violates row-level security policy for table \"notes\""}
HTTP_STATUS:401
#9exit 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 row id=5 (should affect 0 rows) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" "$SUPABASE_URL/rest/v1/notes?id=eq.5" \
  -X PATCH \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $BOB_TOKEN" \
  -H "Content-Type: application/json" -H "Prefer: return=representation" \
  -d '{"title":"hacked-by-bob"}'

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

echo ""
echo "=== Alice tries to reassign her row's user_id to bob (should FAIL due to WITH CHECK) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" "$SUPABASE_URL/rest/v1/notes?id=eq.5" \
  -X PATCH \
  -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 ""
echo "=== Bob tries to delete alice's row id=5 (should affect 0 rows) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" "$SUPABASE_URL/rest/v1/notes?id=eq.5" \
  -X DELETE \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $BOB_TOKEN" \
  -H "Prefer: return=representation"

echo ""
echo "=== Alice deletes her own test row id=5 (cleanup, should succeed) ==="
curl -s -w "\nHTTP_STATUS:%{http_code}\n" "$SUPABASE_URL/rest/v1/notes?id=eq.5" \
  -X DELETE \
  -H "apikey: $SUPABASE_ANON_KEY" -H "Authorization: Bearer $ALICE_TOKEN" \
  -H "Prefer: return=representation"
=== Bob tries to update alice's row id=5 (should affect 0 rows) ===
[]
HTTP_STATUS:200

=== Alice updates her own row id=5 (should succeed) ===
[{"id":5,"user_id":"0c3dd2dd-39fb-4167-82d5-8977bee1a21f","title":"test-own-updated","body":"owned by alice"}]
HTTP_STATUS:200

=== Alice tries to reassign her row's user_id to bob (should FAIL due to WITH CHECK) ===
{"code":"42501","details":null,"hint":null,"message":"new row violates row-level security policy for table \"notes\""}
HTTP_STATUS:403

=== Bob tries to delete alice's row id=5 (should affect 0 rows) ===
[]
HTTP_STATUS:200

=== Alice deletes her own test row id=5 (cleanup, should succeed) ===
[{"id":5,"user_id":"0c3dd2dd-39fb-4167-82d5-8977bee1a21f","title":"test-own-updated","body":"owned by alice"}]
HTTP_STATUS:200
#10exit 0
psql "$SUPABASE_DB_URL" -c "select id, user_id, title, body from public.notes order by id;" 2>&1
rm -f /tmp/alice_token /tmp/bob_token /tmp/alice_id /tmp/bob_id /tmp/rls_notes.sql
 id |               user_id                |    title     |         body         
----+--------------------------------------+--------------+----------------------
  1 | 0c3dd2dd-39fb-4167-82d5-8977bee1a21f | Groceries    | milk, eggs, coffee
  2 | 0c3dd2dd-39fb-4167-82d5-8977bee1a21f | Call plumber | kitchen sink leaks
  3 | bf88dbef-e3e9-4ca9-b6ab-5e30dbcc3a3f | Gym plan     | push pull legs
  4 | bf88dbef-e3e9-4ca9-b6ab-5e30dbcc3a3f | Trip ideas   | mountains in october
(4 rows)

What it said at the end

Original data is intact — the test row I created (id=5) was cleaned up, and alice's/bob's original 4 notes are unchanged. ## Summary I locked down `public.notes` to owner-only access via Postgres Row-Level Security (the mechanism PostgREST/Supabase's REST API enforces on every request): 1. **Enabled and forced RLS** on the table: ```sql ALTER TABLE public.notes ENABLE ROW LEVEL SECURITY; ALTER TABLE public.notes FORCE ROW LEVEL SECURITY; ``` (RLS was previously off with zero policies, which is why every row was exposed to any API key.) 2. **Added four owner-scoped policies**, all restricted to the `authenticated` role and keyed off `auth.uid() = user_id`: - `notes_select_own` (SELECT) — `USING (auth.uid() = user_id)` - `notes_insert_own` (INSERT) — `WITH CHECK (auth.uid() = user_id)` — blocks inserting rows with someone else's `user_id` - `notes_update_own` (UPDATE) — `USING` + `WITH CHECK (auth.uid() = user_id)` — blocks editing others' rows and blocks reassigning a row's `user_id` away from yourself - `notes_delete_own` (DELETE) — `USING (auth.uid() = user_id)` 3. **No policy exists for the `anon` role**, so with RLS enabled, anonymous requests satisfy zero policies and return no rows and cannot write (table-level grants for `anon`/`authenticated` remain as Supabase's defaults; RLS is what actually filters the rows). **Verified end-to-end against the live REST API** with real logins for alice/bob: - Anon `GET /rest/v1/notes` → `[]` - Alice sees only her 2 notes, Bob sees only his 2 notes (confirmed even when explicitly filtering by the other user's `user_id`) - Alice can insert a row with her own `user_id` (201), but inserting with Bob's `user_id` is rejected (403, RLS violation), and anon insert is rejected (401/RLS) - Bob's attempt to UPDATE/DELETE Alice's row affects 0 rows; Alice can update/delete her own row - Alice attempting to change her row's `user_id` to Bob's is rejected (403) by the `WITH CHECK` clause Test row created during verification was deleted afterward; the original 4 notes (2 for alice, 2 for bob) are confirmed untouched.

9 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 0 OK

Check it yourself

Raw transcript · Task definition and verifier · Every attempt