High-Yield Bait Smart Contract Permission Hijacking Scam: Fake Airdrops Inducing Asset Theft via Unauthorized Permissions

Who Gets Targeted

Victims are primarily cryptocurrency holders and Web3 project participants who have some experience with digital assets but often lack a deep understanding of the underlying smart contract mechanisms. Their psychological weaknesses lie in greed for 'high-yield returns' and 'free airdrops,' as well as blind trust when faced with complex authorization prompts. When seeing forged endorsements from project teams or promises of high returns, they are often eager to seize the opportunity and click 'authorize' without carefully verifying the contract call content, ultimately leading to assets being drained and becoming difficult to recover.

骗局怎么运作

• Hackers meticulously forge pages or communities of well-known Web3 projects, spreading advertisements for 'high-value airdrops' or 'high-yield wealth management' on social media like X (Twitter) and within wallets. Exploiting the fear of missing out (FOMO), they lure victims to click links leading to carefully disguised phishing sites, which often mimic official websites and include countdown timers to create a sense of urgency.
• After victims connect their crypto wallets to the phishing site, the system prompts them to perform an 'authorization signature' to claim airdrop tokens. However, this signature is actually a permission grant for a smart contract. Hackers hide traps in the underlying code, requesting the user to grant the contract unlimited spending authority over specific tokens, while the front-end page displays harmless 'claim' text to deceive the user.
• Once the user confirms the malicious signature in their wallet, the hacker's deployed smart contract gains authorization to transfer the user's assets. At this point, the user has neither transferred assets nor seen any anomalies, but the back-end program has automatically recorded the authorization status. When the time is right, it silently transfers all mainstream tokens from the victim's wallet to the hacker's controlled address. The entire process is seamless and rapid.
• Some scams also exploit known vulnerabilities like 'Ill Bloom' or legacy contract bugs to target specific wallet software. Hackers send malicious tokens disguised as airdrops to trigger these vulnerabilities. When users open their wallets and see a 'red dot' notification, the underlying assets have already been authorized for transfer, bypassing the need for manual signatures and completing the asset harvest directly.
• In ecosystems like Solana, scams also involve impersonating project teams to send unsolicited tokens to users' wallets, accompanied by phishing links. When users unknowingly attempt to cash out these 'airdrops' at an exchange, they are guided to a fake decentralized exchange (DEX) page and induced to sign malicious smart contracts, leading to the systematic draining of existing assets in their wallets.
• After assets are transferred, hackers immediately use cross-chain bridges, mixers, or decentralized exchanges to scatter and launder the stolen funds, cutting off on-chain tracking leads. Simultaneously, they quickly shut down the phishing sites and deactivate social media accounts. Victims only discover that assets were authorized to a completely unknown address when checking authorization records later, but due to the irreversible nature of blockchain, recovery is almost hopeless.

红旗信号（看到这些快跑）

• 🚩 Airdrop tokens of unknown origin suddenly appear in the wallet, accompanied by links to unknown third-party websites; this is often an entry point for inducing signatures on malicious contracts.
• 🚩 The wallet displays unusual gas fees or requests for unlimited token spending authority during signature authorization, rather than simple token receipt or transfer transaction records.
• 🚩 The alleged airdrop or high-yield project has not been announced on official core channels, and the official website domain is highly similar to a well-known project but contains subtle typos or exotic top-level domains.
• 🚩 The website uses high-pressure language, such as 'countdown to claim' or 'limited quota,' forcing victims to connect their wallets without verifying the contract code.
• 🚩 The connected wallet displays unexplained pop-up red dots claiming a prize or a large stablecoin reward, requiring the input of a seed phrase or non-standard, complex authorization operations.

真实案例

• In 2026, the Tencent Cloud Developer Community disclosed the '800 Million KRW USDT Phishing Case': The Gangbuk Police Station in Seoul, South Korea, in cooperation with Vietnamese police, cracked a major phishing case. Hackers used high-yield bait to build a fake DeFi project, inducing victims to connect wallets and sign smart contract permissions. The case involved 800 million KRW; victims thought they were participating in staking, but instead, they handed over large-scale USDT spending authority, which was then silently transferred. (Source: https://developer.cloud.tencent.com/article/2634581)
• In 2026, according to crypto media such as WEEX, in an attack event involving the 'Ill Bloom' legacy vulnerability, hackers launched targeted attacks on 2,100 wallets. By sending malicious tokens disguised as red packets or airdrops to trigger old defects, victims were automatically authorized for transfer without manual confirmation, resulting in millions of dollars in cryptocurrency losses. (Source: https://www.weex.com/zh-CN/news/detail/hack-of-2100-wallets-due-to-an-old-bug-ill-bloom-vulnerability-wipes-out-millions-in-cryptocurrency-eyox9htmwhzpqmo3689fyv3z)
• In 2026, a technical article on the Tencent Cloud Developer Community analyzed the Solana chain CJUP fake token incident: Hackers impersonated the Jupiter project team to promote fake airdrops on social networks, directly dropping worthless CJUP tokens into users' wallets and using 'activation/claim' scripts to lure them in. Victims were induced to connect wallets to a high-fidelity fake exchange and sign authorizations, ultimately leading to the transfer of their original SOL assets. The official Jupiter team clarified that no airdrop activities were released that month. (Source: https://developer.cloud.tencent.com.cn/article/2673091)
• In 2026, according to ChainCatcher citing Dongguan Release, Dongguan Hengli police successfully intercepted a virtual currency high-yield scam: Fraudsters used 'high-yield airdrop returns' to induce the victim to make large investments and perform authorization operations. The victim was nearly defrauded of 1.1 million RMB, but police successfully stopped the fund transfer before the transaction occurred. (Source: https://www.chaincatcher.com/article/2281577)

Official Stance

• In 2024, the Tencent Cloud Developer Community released a security research warning titled 'Smart Contract Permission Hijacking Under High-Yield Bait,' pointing out that the trend of fake high-yield platforms in Web3 scenarios using smart contract authorization mechanisms for silent asset theft is spreading rapidly.
• In 2023, the SlowMist security team and major crypto media issued multiple warnings, advising users to be vigilant against 'red dot' pop-ups and unknown airdrop tokens appearing in wallets, emphasizing that these are often phishing attacks using 'permit signatures' by hackers.
• In 2024, the National Anti-Fraud Center and various local public security organs (such as Dongguan Police) reported and intercepted multiple new types of cyber fraud using virtual currency airdrops and high returns as bait, urgently reminding the public not to authorize or connect crypto wallets via unofficial links.

How to Protect Yourself

• ✅ Before participating in any airdrop or wealth management project, always verify the authenticity of the domain through core channels such as official X (Twitter), Discord, or GitHub. Never click on shortened links or unknown URLs that suddenly appear in your wallet.
• ✅ Use professional wallets that support transaction simulation and permission auditing. Carefully check the called contract methods and authorization limits every time you sign an authorization. If a request for unlimited authorization appears, refuse it immediately.
• ✅ Regularly use authorization management tools on blockchain explorers like Etherscan or Solscan to check your wallet's authorization records and promptly revoke permissions for unknown or suspicious smart contracts.
• ✅ Adopt a cold/hot wallet separation strategy for daily asset management. Store large assets only in hardware cold wallets, and keep only small amounts in hot wallets for daily interactions, fundamentally reducing the exposure to losses from a single malicious authorization.