The exploit specifically involves the "RouterProcessor2" contract, which is used to route trades on the SushiSwap exchange.
"It seems the SushiSwap RouterProcessor2 contact has an approve-related bug, which leads to the loss of >$3.3M loss," security firm PeckShield flagged during Asian morning hours on Sunday. Sushi developers later confirmed the exploit.
According to several tweets from multiple security firms, the $3.3 million apparently came from a single user, @0xsifu, a popular pseudonymous trader in Crypto Twitter circles.
DefiLlama developer @0xngmi, who is also pseudonymous, said Sunday that the exploit seemed to affect only users who approved SushiSwap contracts in the past four days.
Meanwhile, SushiSwap head developer Jared Grey asked users to revoke permissions for all contracts on SushiSwap as a security measure, adding the team was "working with security teams to mitigate the issue."
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