Bitcoin, Ether sink as $9m Yearn Finance breach triggers fresh market sell-off

Major cryptocurrencies slumped on Monday as a security breach at decentralized finance (DeFi) platform Yearn Finance, triggered renewed panic across an already fragile market, extending the bruising decline seen through November.

Bitcoin (BTC) slipped more than three percent in early Asian trading hours to hover near $87,000, deepening losses after ending November with a 17.5 percent drop, its worst monthly performance since March.

Ether (ETH) shed about five percent to trade around $2,834, while other major altcoins including SOL, DOGE and XRP plunged more than four percent according to CoinDesk market data.

The slide continues a downtrend fueled by weakening institutional demand and persistent investor caution.

Market sentiment deteriorated further after Yearn Finance disclosed an incident affecting its yETH liquidity pool. The DeFi platform confirmed that its V2 and V3 vaults remained safe but warned that one of the protocol’s pools had been compromised.

Blockchain security firm PeckShield later reported that the attacker minted an unusually large amount of yETH in a single transaction, draining liquidity and siphoning off roughly 1,000 ETH, valued at about $3 million, through crypto mixers.

Read also: Crypto market jumps 3.7% as bitcoin breaks $91,000, ethereum reclaims $3,000

In total, Yearn suffered an estimated $9 million loss from the exploit. The attacker’s wallet, identified as 0xa80d…c822, still holds about $6 million in tokens, investigators said.

The breach underscores rising concerns about DeFi vulnerabilities, arriving just days after leading South Korean exchange Upbit suffered a multi-million-dollar hack.

The Yearn exploit quickly ricocheted across markets, triggering more than $400 million in liquidations of leveraged crypto futures, mostly from long positions betting on a rebound. Data from Coinglass showed traders were caught off guard by the sudden downturn, amplifying price declines across key tokens.

The turbulence caps a difficult period for digital assets, particularly Bitcoin and Ether. Despite briefly recovering from lows near $80,000 to above $90,000 late last month, Bitcoin still closed November sharply lower. Ether’s 22 percent monthly loss marked its weakest performance since February.

Royal Ibeh is a senior journalist with years of experience reporting on Nigeria’s technology and health sectors. She currently covers the Technology and Health beats for BusinessDay newspaper, where she writes in-depth stories on digital innovation, telecom infrastructure, healthcare systems, and public health policies.

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