# Security posture

Holdfast holds real money in an **immutable** contract — once deployed, a bug can
never be patched. This page is an honest account of what has been done to reduce
that risk, **and what has not.** Read it before you deposit.

## ⚠️ Not professionally audited

Holdfast has **not** had a third-party security audit. Automated tools and an
automated test suite are **not a substitute** for a human audit. This is a small,
personal-scale project. **Only lock funds you would be comfortable losing.**

## What has been done

| Check | Status |
|---|---|
| Built on OpenZeppelin (`SafeERC20`, `ReentrancyGuard`) | ✅ |
| Automated tests (33), incl. fuzzing + a reentrancy-attack test | ✅ |
| Full lifecycle proven on Base Sepolia (lock → fee → matured → release) | ✅ |
| Static analysis — Slither 0.11.5 (Trail of Bits) | ✅ 0 high, 0 medium |
| Static analysis — Aderyn 0.6.8 (Cyfrin) | ✅ 0 high, 0 medium |
| Source verified on Basescan | ✅ |
| Ownerless, no admin key, no upgrade path | ✅ by design |

Raw tool output is published alongside the app so you don't have to take our word:
- [`security/slither.txt`](security/slither.txt) — also at `/security/slither.txt` on the live site
- [`security/aderyn.txt`](security/aderyn.txt) — also at `/security/aderyn.txt` on the live site

## The findings, in full

Between them the two tools reported **6 low-severity findings and zero high or
medium.** Every one is a known false-positive for a time-lock or a cosmetic nit:

**Slither**
1. *Dangerous strict equality* (`unlockTime == 0` in `timeRemaining`) — intentional
   sentinel for a non-existent/withdrawn deposit. Correct as written.
2. & 3. *Uses `block.timestamp` for comparisons* (`withdraw`, `timeRemaining`) — the
   generic "validators can nudge the timestamp a few seconds" warning. Irrelevant for
   day-scale locks; comparing `block.timestamp` to an unlock time is the standard,
   correct way to build a time-lock.

**Aderyn**
1. *Large numeric literal* (`10_000` in the fee math) — style suggestion (`1e4`).
   `10_000` is clearer for basis points.
2. *PUSH0 opcode* — warns some exotic chains lack `PUSH0`. **Base supports it**
   (`evm_version = "cancun"`), so this does not apply here.
3. *Unspecific pragma* (`^0.8.24`) — best practice is an exact pin, but `foundry.toml`
   already pins `solc_version = "0.8.24"`, so the compiled bytecode is fixed regardless.

None of these are exploitable and none were changed, because doing so would only alter
style while forcing the already-deployed, verified vaults out of sync with their source.

## Reproduce it yourself

You don't need this repo — pull the verified source straight from Basescan, or use
the copy served at `/TimeLockVault.sol`, then:

```bash
# Slither (pip install slither-analyzer)
slither . --filter-paths "lib/|test/|script/"

# Aderyn (https://github.com/Cyfrin/aderyn)
aderyn --src contracts/ .

# The test suite
make install && make test
```

## Reporting a vulnerability

Found something? Please report it privately to **kp@kpledger.xyz** before disclosing
publicly. The contract is immutable, so a real finding means a redeploy and a warning
to existing depositors — responsible disclosure genuinely matters here.