README.md

vulnerable/unchecked_math

Vulnerability: Integer Overflow

Severity: High

Description

Staking reward calculations use raw * on u64 values. When the stake amount or elapsed ledgers are large, the multiplication silently wraps to a small number, allowing an attacker to claim far less (or far more) than they are owed.

Exploit Scenario

1. Attacker stakes a large amount and waits many ledgers.
2. claim_rewards computes stake * rate * elapsed using unchecked arithmetic.
3. The product overflows u64, wrapping to near zero — reward pool is effectively stolen or the attacker receives an inflated payout depending on wrap direction.

Vulnerable Code

let reward = stake * rate * elapsed; // ❌ silent overflow

Secure Fix

let reward = stake
    .checked_mul(rate)
    .and_then(|v| v.checked_mul(elapsed))
    .expect("reward overflow"); // ✅

See secure/secure_vault for the full corrected implementation.

References

• docs/vulnerabilities.md
• docs/threat_model.md