# Spot the bug: Data Science & ML

> One snippet. Find the bug, or prove there isn't one.

Daily challenge: 2026-08-19 (UTC) · Mid-Level

```python
import hashlib
from sqlalchemy.orm import Session
from models import User

def register_user(db: Session, email: str, password: str) -> User:
    hashed = hashlib.md5(password.encode()).hexdigest()
    user = User(email=email, password_hash=hashed)
    db.add(user)
    db.commit()
    db.refresh(user)
    return user

def verify_password(db: Session, email: str, password: str) -> bool:
    user = db.query(User).filter_by(email=email).first()
    if not user:
        return False
    return user.password_hash == hashlib.md5(password.encode()).hexdigest()
```

## Your verdict

- Security flaw
- Logic bug
- Code style
- No issue

One attempt per day. The answer shows up right after.

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