Can a Decentralized Exchange Be Vulnerable to a 51% Attack?

Yes, a decentralized exchange (DEX) can be vulnerable to a 51% attack, although the attack would target the underlying blockchain rather than the DEX itself. If the blockchain on which the DEX is built is successfully attacked, the attacker could reverse transactions that were made on the DEX.

This could lead to a loss of funds for users of the DEX. To mitigate this risk, DEXs should be built on blockchains with a high hash rate and a strong security model.

What Mechanism on a DEX Makes It Vulnerable to Price Manipulation via Sandwich Attacks?
How Does Network Latency Contribute to Slippage in Decentralized Exchange (DEX) Trading?
Why Is a CEX Order Book Susceptible to Insider Trading Rather than External Front-Running?
What Is a “Re-Entrancy Attack” and Why Is It a Common Smart Contract Vulnerability?
How Is a “Dead Cat Bounce” Different from a True Market Reversal?
Why Is the Constant Sum Model Susceptible to Being Fully Drained When the Price Peg Fails?
What Specific Smart Contract Functions Are Most Susceptible to Sandwich Attacks?
How Does the Settlement Process for a Derivatives Trade Differ between a CEX and a DEX?