Briefing
A sophisticated phishing attack compromised an unidentified crypto investor’s 2-of-4 Safe multi-signature wallet, resulting in the theft of $3.047 million in USDC. The attacker leveraged a meticulously crafted fake Etherscan-verified contract to impersonate a legitimate recipient, disguising a malicious approval within what appeared to be a routine transaction. This incident underscores the escalating complexity of social engineering attacks targeting robust security architectures. The stolen funds were promptly converted to Ethereum and routed through Tornado Cash, obscuring their trail.
Context
Prior to this incident, the digital asset landscape faced persistent threats from various phishing methodologies, including direct wallet drainers and front-end compromises. The prevailing attack surface often includes user interaction points where transaction details can be obfuscated or mimicked. This exploit capitalized on the nuanced trust mechanisms associated with Etherscan verification and multi-send functionalities, exploiting a previously known class of vulnerability related to deceptive contract interactions rather than a direct smart contract flaw.
Analysis
The incident’s technical mechanics involved the attacker deploying a fake Etherscan-verified contract nearly two weeks in advance, programmed with legitimate-looking “batch payment” functions. The compromised system was the user’s perception and scrutiny of transaction details within the Request Finance app interface, coupled with the inherent trust in seemingly verified contracts. The attacker initiated two consecutive transactions where the victim approved transfers to an address that visually mimicked the intended recipient, exploiting the Safe Multi Send mechanism to embed the abnormal approval. This chain of cause and effect demonstrates a sophisticated blend of social engineering and on-chain contract impersonation, enabling the attacker to bypass standard security checks by making the malicious approval appear routine and difficult to detect.
Parameters
- Protocol/Wallet Targeted ∞ Unidentified 2-of-4 Safe multi-signature wallet
- Attack Vector ∞ Sophisticated Phishing via Contract Impersonation and Disguised Approval
- Financial Impact ∞ $3.047 Million USDC
- Blockchain Affected ∞ Ethereum
- Date of Exploit ∞ September 11, 2025
- Forensic Details ∞ Funds swapped to ETH, sent to Tornado Cash; attacker used fake Etherscan-verified contract; leveraged Safe Multi Send mechanism; executed via Request Finance app interface
Outlook
Immediate mitigation for users involves heightened vigilance when approving transactions, scrutinizing contract addresses beyond superficial resemblance, and verifying all details through independent channels. This incident will likely establish new security best practices emphasizing enhanced transaction simulation tools and user education on the subtle indicators of contract impersonation. It highlights a contagion risk for other protocols and users relying on similar multi-send or batch approval mechanisms without robust internal validation processes, necessitating a re-evaluation of UI/UX design to prevent such deceptive interactions.
Verdict
This incident decisively confirms the evolving sophistication of social engineering attacks, demonstrating that even multi-signature protections can be circumvented through meticulously crafted contract impersonation and disguised transaction approvals.
Signal Acquired from ∞ cryptoslate.com
