Meerkat DeFi team briefly rug-pulls $31 million before returning the funds with an odd explanation

The team behind the Meerkat DeFi protocol claimed they had been victims of a hack, but subsequently disappeared from the web after the equivalent of $31 million in Binance Coin (BNB) and BUSD was pulled from the project. Two days later, a developer for the project wrote that the project had been a "test [of] user greed and subjectivity", and aimed to "[help] users realize the potential danger in smart contracts [and] the subjectivity in the audit processes of audit companies." The developer wrote that all victims would be refunded. Some believed that the bizarre "experiment" explanation was to cover that Binance had stepped in to address the scam.

$37.5 million stolen from C.R.E.A.M. lending platform

A hacker was able to code a smart contract that tricked C.R.E.A.M. into believing it was from a trusted source. They were then able to make off with $37.5 million worth of Ethereum and stablecoins in what was only the first of several major exploits of the platform in 2021.

Yearn Finance loses $11 million to a hack

An exploit in Yearn Finance's yDAI vault resulted in an $11 million loss to the platform, though "only" $2.8 million of this went to the hacker.

Tether pays $18.5 million in penalties; NY Attorney General alleges they don't have the cash reserves they claim

The stablecoin Tether swears up and down that it's fully backed by actual currency, but the New York Attorney General doesn't agree. Tether paid $18.5 million in penalties, was banned from trading in New York, and agreed to submit transparency reports for two years in exchange for ending the long-running legal dispute.

PopcornSwap rug pulls

PopcornSwap launched on BNB Chain and then immediately drained its liquidity pool, making off with tokens priced at around $2 million.

Binance stated that they had been able to freeze users' assets on the BNB Chain partway through the incident. However, as of June 2023, Binance had not taken any steps to return the frozen funds to their original owners.

Saddle Finance exploited within hours of launch

The Saddle Finance defi project, a fork of the Curve Finance project, launched on January 20. It promised it would "eliminate slippage".

The project was exploited only hours later, by attackers who stole more than 7.9 BTC (~$275,000) by taking advantage of high slippage on the platform.