plm-lottery/BUGS.md

Known bugs

A second full-codebase audit on 2026-07-27 found 25 further issues (4 critical, 6 high, 7 medium, 8 low), listed below as B-43 … B-49. B-25 through B-42 are fixed (see "Previously fixed" below) — no Critical-, High- or Medium-severity finding remains open; the remaining 7 are Low/hygiene. The 139-test suite was green at the time of the audit, so none of these were caught by existing coverage — every fix lands with a regression test (the eighteen fixes so far brought the suite from 139 to 224).

The recurring pattern across the open findings is worth stating once: the code is rigorous about the failure modes that have actually been hit, and silent about the ones that have not. The payout phase is now fully recoverable; the "drawing" phase (waiting on a block) is now observable (B-36) but still has no equivalent resume-after-restart — see "Known gaps / TODO" in CLAUDE.md, which is also where other by-design limitations (single-shared-token admin auth, single-process assumptions, no user-facing history, etc.) are documented.

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Low / hygiene

B-43 — No HTTP security headers

The Caddyfile sets no CSP, no X-Frame-Options/frame-ancestors, and no HSTS (Caddy does not add it on its own). The JWT lives in localStorage, so any XSS exfiltrates it, and the page is iframeable. Fix: a header block in the Caddyfile with Strict-Transport-Security, X-Content-Type-Options: nosniff, Referrer-Policy and a CSP tight enough for two static pages with no external assets (default-src 'self').

B-44 — README and CLAUDE.md contradict each other

The README says to run uvicorn --reload directly and docker compose run --rm app python scripts/generate_master_key.py; CLAUDE.md says explicitly that neither is supported. Whoever opens the repo reads the README first. Fix: align the README's Quick start with the Docker-only workflow documented in CLAUDE.md and docs/setup.md.

B-45 — Unvalidated and unpaginated admin list endpoints

limit: int = 50 on /admin/rounds and /admin/audit-log has no bounds (-1 means "everything" on SQLite), and /admin/pending-transactions has no limit at all — it grows without end. Fix: Query(default=50, ge=1, le=500) on both, and the same treatment plus a status filter on the pending-transaction list.

B-46 — secrets.compare_digest on a str raises on non-ASCII input

api/routes/admin.py:27 raises TypeError — a 500 instead of a 403 — when the header contains non-ASCII characters. Fix: compare the UTF-8 encoded bytes of both sides.

B-47 — Unbounded String columns for large text

raw_tx_hex (db/models.py:146) and payload_json (:178) should be Text. It works on SQLite and PostgreSQL and breaks elsewhere. Fix: switch both to Text in a migration.

B-48 — No cap on input count in select_utxos

A user with hundreds of small UTXOs builds a huge transaction whose fee — deducted from the bet amount — materially erodes their contribution to the pool, and it can exceed standardness limits. Fix: cap the selected inputs (e.g. 50) and fail with a translatable error suggesting a consolidation, or consolidate the address automatically when the count crosses a threshold.

B-49 — Rollback paths do not publish an SSE update

bets/service.py:_release_failed_bet and withdrawals/service.py:_release_failed_withdrawal restore the balance without calling broadcaster.publish(), so dashboards only find out on their next poll. Fix: one broadcaster.publish() at the end of each, as every other state-changing path already does.

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Previously fixed

• B-25 — the payout had no two-phase write, unlike bets and withdrawals
• B-26 — a payout failure or a process restart could wedge a round in paying_out forever
• B-27 — an RBF bump reset the reconciler's own abandon clock, so a repeatedly-bumped tx was never abandoned
• B-28 — a hostile Electrum server (or a MITM) could single-handedly pick the round's winner
• B-29 — a UTXO absent from one server's listunspent was marked spent immediately, irreversibly, on a single unauthenticated reply
• B-30 — a lost scripthash subscription meant a user's deposits were never credited, with no periodic safety net
• B-31 — resubscribing on reconnect ran serially before anything else started, freezing the chain tip (and so an in-flight draw) for the whole sweep
• B-42 — Swagger/ReDoc/the raw OpenAPI JSON enumerated the entire API surface, admin endpoints included, to anyone who requested them; now off by default and gated behind ENABLE_API_DOCS
• B-32 — an RBF bump could retry forever below BIP125's relay-mandated minimum fee delta, with no ceiling on the fee rate either
• B-33 — POST /auth/login had no rate limiting, so a password could be brute-forced against an enumerable username list
• B-34 — password change/reset didn't invalidate already-issued JWTs, so a stolen token survived a change meant to lock it out
• B-35 — API timestamps round-tripped as naive datetimes, so the frontend parsed them as local time instead of UTC
• B-36 — a stalled draw wait had no timeout, no log, and no audit trail, so a frozen round showed nothing in /admin
• B-37 — a withdrawal covered by unconfirmed change answered "insufficient balance" instead of distinguishing it from actually having no funds
• B-38 — the SSE subscriber cap was global, so one client opening enough connections degraded every other user to polling
• B-39 — SQLite ran without WAL or a busy_timeout, so a writer could block every reader and a second writer failed immediately instead of waiting
• B-40 — bump_fee held a DB session open across N slow network calls, and computed a prevout's value from a server-reported float instead of an exact integer
• B-41 — confirmation/reconciliation depended on a verbose blockchain.transaction.get reply many Electrum servers reject, and abandonment relied on fragile substring-matching of an error message

See git history for the fix-by-fix breakdown (commits f13f685, 50a43ae, 933760e, and the B-28/B-29/B-30/B-31/B-32/B-33/B-34/B-35/B-36/B-37/B-38/B-39/B-40/B-41/B-42 fixes). Suite grew from 139 to 224 tests over the eighteen.

A full-codebase audit on 2026-07-26 (commit d4e0974) found 24 bugs across every Python module under app/, both static frontends, and the Docker/Caddy deployment — 5 critical, 7 high, 7 medium, 5 low. All 24 were fixed and verified against the current code on 2026-07-27; the fixes are covered by the regression suite (grew from 79 to 139 tests) and five of them were additionally confirmed against a real mainnet deployment (see git history between fb734bb (documenting the findings) and 845ba98 (recording the audit outcome) for the fix-by-fix breakdown — each commit message names the bugs it closes and where their tests live).