So you’ve built an exciting new decentralized application and are ready to launch it on the blockchain. But before you do, it’s crucial to ensure your dapp is secure and hardened against the many threats lurking out there. Hackers are targeting dapps more than ever, looking to exploit vulnerabilities to steal funds and data. You’ve spent months building your dapp, so you’ll want to protect all that hard work.
Follow these 10 blockchain security tips to fortify your dapp before launch. Whether you’re building on Ethereum, EOS, Tron or another network, security should be at the front of your mind. These pro tips from the experts will help boost your dapp’s defenses and give users peace of mind their digital assets and information are safe. Dapp security is a journey, not a destination, so keep learning and improving to stay ahead of the hackers. Now, let’s dive in and see how to lock down your dapp!
Use a Secure Coding Language Like Rust or Go
If you’re building a dapp, security should be a top priority from day one. Using a secure coding language like Rust or Go is a great place to start. These languages were designed with safety and security in mind, reducing vulnerabilities like buffer overflows that can lead to things like DDoS attacks.
Go, developed by Google, provides static typing, garbage collection, structural typing, and CSP-style concurrency. This means fewer headaches debugging and fewer opportunities for hackers to exploit your code.
Rust takes things a step further with its ownership, borrowing, and lifetimes model which ensures memory safety and thread safety. The Rust compiler will actually refuse to compile code with unsafe behavior, eliminating entire classes of vulnerabilities.
Of course, the language itself is only part of the equation. Some other tips for building a secure dapp:
Keep dependencies up to date. Outdated libraries are a common attack vector.
Use an open source framework. Popular frameworks like OpenZeppelin have been battle-tested and audited.
Write tests for your smart contracts. Unit tests can identify unintended behavior before hackers do.
Consider using a bug bounty program. Crowdsourcing security reviews of your code is an effective way to find vulnerabilities.
Get regular audits of critical smart contracts. For high risk or high value dapps, a professional audit should be part of the development process.
Use multiple signatures for large transactions. Requiring multiple sign-offs prevents a single compromised account from draining funds.
Educate your users about phishing and scams. Humans are often the weakest point in any system, so user education is key.
By making security a priority in your dapp design and development, you’ll build confidence in your platform and avoid the headaches of compromised accounts or stolen funds down the road. Better safe than sorry!
Properly Manage Keys and Secrets
Properly managing your keys and secrets is one of the most important things you can do to secure your Dapp. If hackers gain access to these, your Dapp and user funds are at risk.
Keep Keys Offline
Never store private keys online or on a network-connected device. Generate keys on an offline device and keep backups in a secure, physical location.
Use a Hardware Wallet
Hardware wallets are one of the most secure ways to store keys. They keep keys offline while allowing you to sign transactions. Popular options like Ledger and Trezor are very secure.
Use Strong Passwords
Use long, complex, unique passwords to encrypt any keys or secrets you store digitally. Never reuse the same password across accounts. Consider using a password manager to help generate and remember secure passwords.
Be Careful When Exporting Keys
Only export private keys when absolutely necessary. When exporting, encrypt the keys and store them on a USB drive that is kept offline. Delete the keys from the exporting device immediately after.
Separate Keys by Environment
Use different keys for development, testing and production environments. Never deploy contracts to a live network with test keys.
Restrict Access to Keys
Only share private keys with developers who need access. Use a minimal set of keys for deployment to limit exposure. Consider using a multisig wallet which requires multiple signatures to authorize transactions.
Monitor for Key Compromise
Actively monitor for unauthorized access to keys or funds. Use blockchain explorers to review transactions and look for any unauthorized transfers. Be on alert for phishing emails or malicious software targeting your keys.
By properly managing your keys and secrets, you can help ensure your Dapp and user funds remain secure. Make security a priority in your development process and be diligent in monitoring for threats. The effort will be well worth it.
Implement Access Controls and Permissions
Implement Access Controls and Permissions
When building a dApp, you’ll want to implement strict access controls to limit what users can do and see. This helps prevent unauthorized access and protects sensitive data.
As a developer, think about what different types of users will interact with your dApp. You may have regular users, administrators, moderators, etc. Create user roles that represent these groups and assign permissions to each role. For example, regular users may only be able to view and comment on content, moderators can edit and remove content, and admins have full control.
Use a hierarchical permission system so higher-level roles inherit the permissions of lower levels. This makes management easier since you only have to update permissions in one place.
For permissions, consider what resources users will access (contracts, files, accounts) and what actions are allowed (view, edit, delete). Map out a permission matrix to define who can do what. Some examples:
- Regular users:
› View public contracts
› Comment on posts
- Moderators:
› Edit and remove public contracts
› Ban users
› All regular user permissions
- Admins:
› Deploy new contracts
› Grant and revoke user roles
› All moderator permissions
When a user interacts with your dApp, check their role and permissions to verify the action is allowed. For example, before executing a contract function, ensure the user’s role has permission to call that function. If not, throw an error.
Following security best practices like role-based access control will make your dApp more robust and help gain user trust. Be thoughtful about how you design your permission system—it’s one of the most important parts of building a secure dApp.
Validate Inputs and Outputs
A key part of securing your decentralized application (Dapp) is validating all inputs and outputs. As the developer, you need to assume that malicious actors will try to exploit your system by entering bad data or tampering with outputs. Follow these tips to strengthen your Dapp’s validation processes.
Double check all inputs. Scrutinize any data entered by users before using it for computations or storing it on the blockchain. Make sure inputs match the expected data type and value range to avoid unintended behavior from your Dapp. For example, if you expect a number between 1 to 10, ensure the input is actually a number in that range.
Sanitize outputs before displaying them. When presenting data to users that was retrieved from the blockchain or computed by your Dapp, sanitize it first. Strip out any HTML/CSS or JavaScript that could be used for cross-site scripting attacks if displayed on your interface. Encode special characters as well.
Implement replay attack prevention. Blockchain transactions can be replayed by attackers to manipulate your Dapp. Use mechanisms like timestamps, nonces (numbers used once), or sequence numbers to prevent replay attacks. Each transaction should be unique so it cannot be re-executed.
Validate callback URLs. If your Dapp sends data to an external system via a callback URL, ensure the URL is legitimate first. Malicious users may enter a URL pointing to their own server to steal data from your Dapp.
Check signatures and authorizations. For any transaction, input, or output that requires a signature for verification or authorization, properly validate it before accepting it as valid. Failing to validate signatures is an easy way for hackers to circumvent your system by spoofing identities.
Monitor for anomalies. Set limits for normal behavior in your Dapp like maximum transaction amounts or data entry volumes over time windows. Monitor for activity that exceeds those limits which could indicate an attack. Build alerts to notify you of any anomalies so you can take action.
By rigorously validating all inputs and outputs in your Dapp and monitoring for suspicious activity, you’ll make it far more difficult for hackers and scammers to compromise your system. Diligence in this area will give users greater confidence in your Dapp’s security.
Use Audited and Verified Smart Contracts
Using audited and verified smart contracts is one of the best ways to improve the security of your decentralized application (dapp). An audited smart contract is one that has been rigorously tested by blockchain security experts to identify and patch any potential vulnerabilities that could be exploited. Even verified smart contracts that have been deemed “secure” should still be audited since new security risks are constantly emerging in the blockchain space.
As a dapp developer, you should make auditing and verifying your smart contracts a top priority. Here are a few reasons why:
Avoid Catastrophic Loss of Funds
Unaudited smart contracts can contain flaws that allow hackers to steal cryptocurrency or tokens. By auditing your contracts, you reduce the risk of a major security event that results in a loss of funds for your users.
Build Trust in Your Dapp
Having audited and verified smart contracts establishes credibility and trust in your dapp. Users will feel more confident interacting with and investing in your dapp knowing that its security has been validated by experts. This can help drive greater adoption and usage of your decentralized application.
Stay Ahead of Emerging Threats
The techniques used by hackers to compromise smart contracts are always changing. Audits help ensure your contracts can withstand the latest types of attacks and exploit methods. Auditors are constantly researching new potential vulnerabilities, so they can recommend fixes to keep your dapp secure even as the threat landscape evolves.
Avoid Legal and Regulatory Issues
In some jurisdictions, dapp developers may face legal liability for security breaches or loss of funds if proper security controls and audits were not in place. Auditing your smart contracts helps show regulators and authorities that you made reasonable security efforts and took appropriate precautions to safeguard users and their digital assets.
Auditing and verifying your smart contracts should be an integral part of your dapp’s security strategy. Make it a priority to have all of your contracts thoroughly reviewed and tested before launching your decentralized application. The time and resources invested upfront can help avoid catastrophic disasters down the road.
Adopt Formal Verification for Smart Contracts
Formal verification is a process that mathematically proves that a smart contract will behave as intended. It checks for hidden bugs and vulnerabilities to ensure your Dapp is secure.
Use a Verification Framework
Frameworks like OpenZeppelin’s ZeppelinOS and runtime verification’s KEVM make the verification process easier. They allow you to annotate your smart contracts to express properties about their behavior. The framework then checks that the implementation satisfies the properties.
Specify Invariants
Invariants are conditions that should always be true. For example, you could specify that a contract’s balance should never go negative. The verification tool will throw an error if any transaction could violate an invariant. This helps catch edge cases you may have missed.
Prove Important Properties
Prove critical properties about your contract to mathematically guarantee its correctness. For example, prove that only authorized accounts can call certain functions or that the total supply of tokens does not change unexpectedly. The more you can prove, the more secure your Dapp will be.
Check Effects on the EVM
EVM, or Ethereum Virtual Machine, effects include how much gas is used, how storage is accessed, and how the contract’s state variables change. Check that there are no unintended side effects that could impact security or be exploited.
Review the Formal Proofs
Don’t just rely on the tool – review the actual formal proofs it generates to make sure you understand why the properties hold. Look for any unverified areas of the contract that still need checking. Formal verification does not prove a contract is 100% secure, so manual review is important.
Continuously Verify
Run verification regularly as you continue to develop, update and audit your smart contracts. New releases could introduce new vulnerabilities, so continuous verification helps catch issues early on.
By adopting formal verification and following these best practices, you’ll build mathematically provable security into your Dapp from the start. While not a silver bullet, formal verification significantly reduces risks and provides strong guarantees about how your smart contracts will actually behave.
Perform Regular Security Audits and Testing
To keep your decentralized application (dapp) secure, regular security audits and testing are essential. As a blockchain developer, it’s your responsibility to routinely check for any vulnerabilities or weaknesses that could be exploited.
Performing frequent security checks on your dapp and smart contracts will help identify risks early on so you can take appropriate action.
Conduct Code Reviews
A code review is when developers evaluate each other’s code to find potential issues. Have your team members review code regularly, especially before launching any updates. Fresh eyes may spot something you missed. Look for any code that could enable hacks like phishing, malware, or theft if misused.
Do Penetration Testing
Penetration testing, or pen testing, simulates hacker attacks to locate vulnerabilities. Hire an outside pen testing service to attempt penetrating your dapp system. They can try common attacks like SQL injections, cross-site scripting, and DDoS attacks. Fix any vulnerabilities found right away. Regular pen testing, like quarterly or after major code changes, is ideal.
Check for Known Vulnerabilities
Software and platforms used in your dapp may contain known security vulnerabilities that could threaten your system if unpatched. Routinely scan your dapp for any known vulnerabilities in all integrated software and frameworks. Most have automated scanners to detect weaknesses, so run them frequently, especially after updates.
Review Access Controls and Accounts
Double check that your dapp’s user access controls, permissions, and account management features are secure and functioning properly. Make sure user accounts cannot be accessed or manipulated without the proper credentials. Two-factor authentication on accounts is also a good security practice whenever possible.
Test Edge and Failure Cases
Try to “break” your dapp by testing edge and failure cases. See what happens when users enter bad data, overload systems, access unauthorized features, or manipulate the dapp in unexpected ways. Look for how the dapp responds and fails, then build in measures to prevent or mitigate issues. Continually test new edge and failure cases as you make updates.
Regularly auditing your dapp and smart contract security may seem tedious, but it’s the only way to stay on top of vulnerabilities that could threaten users. Make security checks a priority in your development roadmap to keep your dapp as hack-proof as possible. Stay up-to-date with the latest blockchain threats and security best practices to fortify your dapp against them.
Monitor Activity and Events on the Blockchain
Monitor Activity and Events on the Blockchain
Keeping an eye on your dapp’s activity and events on the blockchain is crucial. This helps identify any suspicious behavior early on so you can take action immediately.
Check your dapp’s transactions, contracts, and events regularly. Look for any unusual spikes in volume or frequency, as this could indicate an attack. Monitor gas usage as well to detect inefficient code or potential infinite loops.
Review your smart contract events and logs. Look for irregular events that could signal unauthorized access or attempts to exploit vulnerabilities in your code. Blockchain explorers and analytics tools make event monitoring a straightforward process.
Inspect the contents of transactions and contract calls. Malicious actors may try to pass invalid arguments or values to compromise your dapp. Closely scrutinize transactions from unknown or suspicious accounts.
Use blockchain monitoring services for enhanced visibility. These services analyze blockchain data to detect risks like stolen funds, phishing scams, money laundering, and other fraudulent activities. They can alert you to anomalous behavior associated with your dapp right away.
Check forums, blogs, and social media for mentions of your dapp. Look for reports of potential vulnerabilities, unresolved issues, or exploits that could threaten your users. Address any valid concerns as soon as possible.
Review your dapp’s smart contracts for new vulnerabilities. As blockchain technologies evolve, new ways to exploit smart contract weaknesses emerge. Conduct regular audits and security assessments of your dapp to identify any flaws before attackers can find them.
Monitoring your dapp around the clock may seem like a lot of work, but it’s the only way to keep users and funds safe while building trust in your project. With vigilance and the right tools, you can fortify your dapp’s defenses and respond quickly in the event of malicious activity. Staying one step ahead of the bad actors will give your users peace of mind that their digital assets and information are in good hands.
Educate Your Team on Security Best Practices
Educating your team on security best practices is crucial for building a robust dapp. As a project leader, make sure all developers and team members understand the importance of security and follow recommended practices.
Do Your Own Research
Encourage team members to stay up-to-date with the latest blockchain security risks and recommendations. Share the most recent reports, whitepapers and studies on key topics like smart contract security, wallet management, and vulnerability detection.
Implement Secure Coding Standards
Work together to establish secure coding standards for your project based on industry best practices. Require things like input validation, error handling, modularity, and least privilege. Review code regularly to ensure standards are being followed.
Promote a Security Mindset
Foster a culture where security is a top priority, not an afterthought. Discuss possible attack vectors and scenarios, and brainstorm ways to mitigate risks. Challenge developers to think like malicious hackers to uncover any weaknesses or loopholes before launching.
Provide Ongoing Security Training
Invest in continuous education and professional development around blockchain security. This could include formal certifications, online courses, conference presentations, or internal lunch-and-learns. Staying up-to-date with the latest risks, tools, and techniques will make your dapp much more robust.
Do Penetration Testing and Audits
Conduct regular penetration tests, audits, and code reviews to uncover vulnerabilities before they can be exploited. Fix any issues immediately and use them as an opportunity to improve secure coding practices. Independent audits from external experts can also provide an objective assessment of your dapp’s security.
Educating and engaging your team in security best practices is essential for building a dapp that users can trust. Promoting a culture of continuous learning and improvement around blockchain security will help ensure your project is as protected as possible from threats. After all, security is a team effort – make it a priority and get everyone on board!
Conclusion
So there you have it, 10 tips to help you lock down your decentralized app and give users peace of mind. Security is an ever-evolving challenge, but keeping these best practices in mind will put you well ahead of the curve. Stay vigilant, keep learning, and build with safety at the forefront. The blockchain space is still new, wild territory, but you have the chance to be a pioneer who gets it right the first time. Keep at it, you’ve got this! With a little elbow grease and a lot of double-checking your work, you’ll be churning out dapps that are as secure as a blockchain itself. Now get to work – the future is calling and they want dapps that will stand the test of time. You’ve got the tools and knowledge to deliver, so go forth and build something unstoppable!
