Blockchain analytics firm Bubblemaps reported a $4 million Sybil attack on the AVNT token airdrop, with tokens subsequently liquidated on Binance, raising concerns about airdrop security.

Executive Summary

Blockchain analytics firm Bubblemaps has identified a Sybil attack that siphoned approximately $4 million from the recent AVNT token airdrop. The acquired tokens were subsequently transferred to and sold on the Binance exchange. This event highlights persistent vulnerabilities in token distribution mechanisms and intensifies scrutiny on protocols' Sybil resistance measures and exchange security protocols.

The Event in Detail

Bubblemaps reported that an entity exploited the AVNT token airdrop to gain $4 million. The attack involved over 300 dormant wallets, exhibiting patterns consistent with a previous MYX token distribution incident, suggesting a coordinated and sophisticated effort. Following the acquisition, all AVNT tokens were transferred to the Binance exchange and liquidated.

Avantis, a derivatives trading platform on the Base ecosystem, had launched its AVNT token airdrop checker on September 7, with claims commencing September 9. The project had announced a total supply of 1 billion AVNT tokens, allocating 51% to its community, with 12.5% specifically for the airdrop. Earlier in June, Avantis successfully completed an $8 million Series A funding round, led by Founders Fund and Pantera Capital, with additional participation from Symbolic Capital, SALT Fund, and Flowdesk.

Upon its listing on exchanges including Binance, Bybit, and MEXC, the AVNT token did not sustain initial gains, trading approximately 10% below its listing price at around $0.27. This decline was attributed to profit-taking by early investors and distributions via other platforms.

Market Implications

This incident is expected to negatively impact AVNT's market reputation and token value in the short term. It underscores the critical necessity for more robust Sybil resistance mechanisms in future airdrops. For major exchanges like Binance, it prompts a re-evaluation of current systems designed to detect and prevent the liquidation of tokens obtained through illicit means, despite Binance's reported $4.2 billion in potential loss prevention and significant investments in AI-powered fraud detection in 2024. The scale of this attack, coupled with previous incidents such as the alleged $170 million Sybil attack on the MYX airdrop, indicates a growing sophistication among attackers targeting token distributions.

Broader Context

The landscape of crypto airdrop farming has evolved into an industrialized activity. Professional farmers now deploy hundreds of scripted wallets to accumulate airdrop points. In response, projects such as Arbitrum (ARB) and Optimism (OP) have implemented quadratic reward formulas and blacklisted suspicious wallet clusters. More advanced strategies, like those adopted by Celestia (TIA) and EigenLayer, incorporate off-chain metrics such, as GitHub contribution scores, to identify legitimate participants.

The industry is shifting towards "fairdrops," which prioritize rewarding genuine engagement and penalizing bot activity. Modern airdrop projects employ sophisticated detection techniques, including Graph Clustering Analysis to identify interconnected wallet clusters, Behavioral Entropy Scoring to favor human-like random activity, and Cross-Chain Validation to authenticate wallets active across multiple blockchains and decentralized applications. These measures aim to maximize human recipients, reduce the return on investment for Sybil attackers, and ensure high-quality user acquisition, reflecting an industry-wide effort to counter increasingly complex exploitation attempts in the Web3 ecosystem.