Blockchain technology is fundamentally designed to be highly secure through its structural reliance on advanced cryptography, decentralized network architecture, and consensus mechanisms, but it is not entirely immune to risks or vulnerabilities. Its primary security strength lies in its immutability; once data is verified and cryptographically linked to the preceding block, altering past transaction records requires an impossibly massive amount of computational power to rewrite the entire chain, protecting against unilateral tampering. Additionally, public blockchains distribute their ledgers across thousands of independent nodes globally, eliminating a single central point of failure that hackers could target to bring down the network. However, the ecosystem interacting with the blockchain often introduces significant security flaws, such as poorly audited smart contracts that contain exploitable code, vulnerable cross-chain bridges, and centralized cryptocurrency exchanges that can be hacked. Furthermore, individual users face immense security burdens because the loss or theft of cryptographic private keys results in an irreversible loss of digital assets, meaning that while the underlying blockchain protocol is incredibly robust, the surrounding infrastructure remains a frequent target for malicious actors.