The Ethereum-based hot wallet of decentralized exchange FixedFloat experienced a series of dubious transactions resulting in the withdrawal of $2.8 million over the past day, as reported by Web3 security firm Cyvers.

In response to this development, stablecoin issuer Tether took action by blocking ten addresses associated with these withdrawals, effectively freezing approximately $400,000 worth of USDT tokens, according to blockchain security firm Peckshield.

Regarding FixedFloat's "suspicious" transactions, Cyvers stated:

"Approximately 14 hours ago, a significant $2.8 million was withdrawn from [FixedFloat's] hot wallet on the ETH chain. The funds were directed to a suspicious address, which subsequently received various digital assets including ETH, USDT, WETH, DAI, and USDC."

Subsequently, these assets were exchanged into Ethereum through a decentralized exchange (DEX) before being moved to the eXch exchange. Following these transactions, the hot wallet ceased functioning, leading the exchange's website to enter maintenance mode.

While FixedFloat has not publicly commented on these transactions, the initiation of maintenance mode on its website mirrors the response observed after a previous security incident in February.

During that incident, the exchange lost $26 million due to an access control issue, prompting it to transition its domain from fixedfloat.com to ff.io. The team emphasized the importance of a shorter domain name in reducing phishing risks and improving user accessibility.

Tether took proactive measures by freezing the addresses associated with these suspicious transactions on FixedFloat.

As of press time, Tether has not responded to CryptoSlate's request for comment.

In the past year, Tether has intensified efforts to crack down on addresses involved in illicit activities. Notably, the company proactively froze the address of a hacker who exploited Ledger's Connect Kit library.

Additionally, Tether has collaborated with regulatory agencies worldwide to recover stolen funds from fraudsters and malicious actors.

However, despite these efforts, there are allegations that hostile actors increasingly favor the USDT stablecoin.