Unhackable. Immutable. Fraud-proof. These terms are frequently used to describe cryptocurrencies and the blockchain technology that underpins them. Together, they imply that a high degree of safety accompanies cryptocurrencies and blockchain ledgers. But is this understanding supported by the facts, or is it more based on the promise and theoretical construction of blockchain and cryptocurrencies? To better answer this question, we have compiled and analyzed existing research on initial coin offerings, security offerings, blockchain hacks and thefts, and data breaches of blockchain-based platforms and digital wallets. In contrast to the popular press, we find that in practice, blockchain and cryptocurrencies are more prone to malfeasance, fraud, and manipulation than is commonly understood. The security and trust provided by blockchain as a technology tool are only as secure as the underlying code that establishes the blockchain, and the value derived from cryptocurrencies is only as trustworthy as the entity developing the cryptocurrency. Neither are without their vulnerabilities. Skepticism and proper due diligence should be maintained for any entity looking to utilize blockchain technology or invest in cryptocurrencies.