Web3 Trading Security Guide: Building an Autonomous and Controllable Defense System

With the continuous development of the on-chain ecosystem, on-chain transactions have become an indispensable part of daily operations for Web3 users. User assets are accelerating their migration from centralized platforms to decentralized networks, which also means that the responsibility for asset security is shifting from the platform to the users themselves. In the on-chain environment, users must take responsibility for every interaction, including importing wallets, accessing DApps, signing authorizations, and initiating transactions. Any careless operation may lead to serious consequences such as private key leakage, authorization abuse, or phishing attacks.

Although mainstream wallet plugins and browsers are gradually integrating features such as phishing detection and risk alerts, relying solely on passive defenses provided by tools is still insufficient to completely avoid risks in the face of increasingly complex attack methods. To help users more clearly identify potential risk points in on-chain transactions, we have compiled a systematic on-chain transaction security guide based on practical experience, outlining high-risk scenarios throughout the entire process, and combined with protective suggestions and tool usage tips. This guide aims to assist every Web3 user in building a "self-controllable" security defense.

Core principles of secure trading:

• Refuse to sign blindly: Do not sign transactions or messages that you do not understand.
• Repeated Verification: Before making any transaction, be sure to verify the accuracy of the relevant information multiple times.

1. Safe Trading Recommendations

The key to protecting digital assets lies in secure transactions. Research shows that using secure wallets and two-factor authentication (2FA) can significantly reduce risks. Specific recommendations are as follows:

1. Choose a secure wallet: Prioritize reputable wallet providers, such as certain well-known hardware wallets or software wallets. Hardware wallets offer offline storage, reducing the risk of online attacks, making them suitable for storing large amounts of assets.

2. Carefully verify the transaction details: Before confirming the transaction, be sure to verify the receiving address, amount, and network (e.g., ensure you are using the correct chain) to avoid losses due to input errors.

3. Enable Two-Factor Authentication: If the trading platform or wallet supports 2FA, be sure to enable it to enhance account security, especially when using hot wallets.

4. Avoid using public Wi-Fi: Do not conduct transactions on public Wi-Fi networks to prevent phishing attacks and man-in-the-middle attacks.

2. Safe Trading Operation Guide

A complete DApp transaction process involves multiple stages: wallet installation, accessing the DApp, connecting the wallet, message signing, transaction signing, and post-transaction processing. Each stage carries certain security risks, and the following will introduce the precautions to take during actual operations.

1. Wallet Installation

Currently, DApps mainly interact through browser extension wallets. Popular wallets commonly used on EVM chains include certain well-known extension wallets.

When installing the Chrome extension wallet, you should download it from the official app store to avoid installation from third-party websites, which may lead to the installation of wallet software with backdoors. Users who are able to should consider using a hardware wallet in conjunction to further enhance the overall security of private key storage.

When backing up the seed phrase (usually a recovery phrase of 12-24 words), it is recommended to store it in a secure physical location, away from digital devices, such as writing it on paper and keeping it in a safe.

2. Access DApp

Phishing is a common tactic in Web3 attacks. A typical case involves luring users to visit a phishing DApp under the guise of an airdrop, where users are induced to sign token authorizations, transfer transactions, or token authorization signatures after connecting their wallets, resulting in asset loss.

Before accessing the DApp, you should confirm the correctness of the URL. Suggestion:

• Avoid accessing directly through search engines
• Be cautious when clicking links in social media.
• Verify the correctness of the DApp website from multiple sources.
• Add secure websites to browser bookmarks

After opening the DApp webpage, a security check of the address bar is required:

• Check if the domain name and website appear to be counterfeit.
• Confirm if it is an HTTPS link, the browser should display a lock icon.

3. Connect Wallet

After entering the DApp, the wallet connection operation may be triggered automatically or after actively clicking Connect. The plugin wallet will perform some checks and display information about the current DApp.

After connecting the wallet, the DApp typically does not actively invoke the plugin wallet when the user has no other actions. If the website frequently prompts the wallet to sign messages or transactions after logging in, or continues to pop up signature requests even after refusing to sign, this is likely a sign of a phishing site and should be handled with caution.

4. Message Signature

In extreme cases, such as when an attacker successfully breaches the official website of the protocol or replaces the page content through attacks like front-end hijacking, it is difficult for ordinary users to assess the security of the website.

At this point, the signature of the plugin wallet becomes the last line of defense for users to protect their assets. As long as malicious signatures are rejected, asset losses can be avoided. Users should carefully review the content of the signature when signing any message or transaction, and refuse to sign blindly.

Common types of signatures include:

• eth_sign: Sign hash data
• personal_sign: Signs plaintext information, commonly used for user login verification or consent agreement confirmation.
• eth_signTypedData (EIP-712): Sign structured data, commonly used for ERC20 Permit, NFT listings, etc.

5. Transaction Signature

Transaction signatures are used to authorize blockchain transactions, such as transfers or invoking smart contracts. Users sign with their private keys, and the network verifies the validity of the transaction. Many wallet plugins decode the message to be signed and display relevant content; users must adhere to the principle of not signing blindly. Security advice:

• Carefully check the recipient's address, amount, and network to avoid errors.
• It is recommended to use offline signing for large transactions to reduce the risk of online attacks.
• Pay attention to gas fees, ensure they are reasonable, and guard against scams.

For users with certain technical abilities, a manual inspection method can be employed: copy the interactive target contract address into a blockchain explorer for review, mainly checking whether the contract is open source, whether there has been a large number of transactions recently, and whether the explorer has marked the address with official or malicious labels, etc.

6. Post-Trade Processing

Even if you successfully avoid phishing websites and malicious signatures, risk management is still required after transactions.

After the transaction, you should promptly check the on-chain status to confirm whether it is consistent with the expected state at the time of signing. If any anomalies are found, take timely actions such as asset transfer and authorization revocation to mitigate losses.

ERC20 approval management is equally important. In certain cases, after users authorize tokens to contracts, these contracts may be attacked years later, and attackers can exploit the authorized limits to steal user funds. To prevent such situations, it is recommended to follow the standards below:

• Minimized Authorization: Limit the number of tokens authorized according to transaction needs to avoid using the default unlimited authorization.
• Timely revoke unnecessary authorizations: Regularly check the authorization status of addresses, revoke authorizations for agreements that have not interacted for a long time, and prevent asset losses caused by protocol vulnerabilities.

3. Capital Isolation Strategy

Even with risk awareness and adequate preventive measures, it is recommended to implement effective capital isolation to reduce the extent of losses in extreme situations. The recommended strategies are as follows:

• Use multi-signature wallets or cold wallets to store large amounts of assets
• Use a plugin wallet or EOA wallet as a hot wallet for daily interactions.
• Regularly change hot wallet addresses to avoid prolonged exposure to risky environments.

If you unfortunately encounter phishing, it is recommended to take the following measures immediately to reduce losses:

• Use professional tools to revoke high-risk authorizations
• If a permit signature has been signed but the asset has not yet been transferred, a new signature can be initiated immediately to invalidate the old signature nonce.
• If necessary, quickly transfer the remaining assets to a new address or cold wallet.

4. Safely Participate in Airdrop Activities

Airdrops are a common method for promoting blockchain projects, but they also come with potential risks. Here are a few suggestions:

• Project Background Research: Ensure the project has a clear white paper, publicly available team information, and a good community reputation.
• Use a dedicated address: Register a dedicated wallet and email to isolate risks from the main account.
• Be cautious when clicking links: Obtain airdrop information only through official channels to avoid clicking on suspicious links in social media.

5. Selection and Usage Recommendations for Plugin Tools

Given the extensive content of blockchain security guidelines, it may be difficult to conduct thorough checks for every interaction, making the selection of secure plugins crucial for assisting in risk assessment. The specific recommendations are as follows:

• Use trusted extensions: Prefer widely used and well-recognized browser extensions that provide wallet functionality and support DApp interactions.
• Check Ratings: Before installing a new plugin, check the user ratings and number of installations. A high rating and a large number of installations usually indicate that the plugin is more reliable, reducing the risk of malicious code.
• Keep updated: Regularly update plugins to get the latest security features and fixes. Expired plugins may have known vulnerabilities that can be exploited by attackers.

VI. Conclusion

By following the above security trading guidelines, users can interact more confidently in an increasingly complex blockchain ecosystem, effectively enhancing their asset protection capabilities. Although blockchain technology is characterized by its core advantages of decentralization and transparency, it also means that users must independently cope with multiple risks, including signature phishing, private key leakage, and malicious DApps.

To achieve true security on the blockchain, merely relying on tool reminders is far from enough; establishing a systematic security awareness and operational habits is key. By using hardware wallets, implementing fund isolation strategies, regularly checking authorizations, and updating plugins as protective measures, and by adhering to the principles of "multi-verification, rejecting blind signing, and fund isolation" in transaction operations, we can truly achieve "freedom and security on the blockchain."