What Is the Primary Difference between PoW and PoS in Terms of Security Vulnerability?

Proof-of-Work (PoW) security relies on computational power (hashrate) and energy expenditure, making it vulnerable to 51% attacks via hashrate acquisition. Proof-of-Stake (PoS) security relies on economic stake (the amount of native coin held and locked up).

The PoS equivalent of a 51% attack is a "51% stake attack" or "Long-Range Attack," where an attacker needs to control a majority of the staked coins. PoS has a higher economic cost for a successful attack, as the attacker's stake can be "slashed" or destroyed, creating a stronger financial disincentive.