The hidden dangers of front-end attacks in crypto: the case for enhanced Web3 penetration testing
Introduction
We are entering another bull market, and blockchain technology keeps moving into new industries, so the security of blockchain applications matters more than ever.
Most of the attention has gone to smart contract audits. Meanwhile a growing number of front-end attacks in the crypto world pose a significant threat that often goes unnoticed. Smart contract audits alone cannot address this kind of vulnerability, which is why web3 penetration testing is needed as well.
Understanding front-end attacks
Front-end attacks in blockchain and crypto projects occur when malicious actors exploit vulnerabilities in the user interface components of dApps, leaving the underlying smart contracts untouched. Unlike smart contract vulnerabilities, which involve the blockchain’s operational code, front-end attacks typically manipulate web elements. They include XSS, CSRF and SQL attacks, as well as third party plug-in vulnerabilities and security misconfigurations, and they are used to reroute funds or steal sensitive information.
Recent incidents include the hacks on Velodrome and Aerodrome. Attackers exploited front-end weaknesses to execute unauthorized transactions, bypassing the strong smart contract measures in place. Front-end vulnerabilities can do just as much damage as those in smart contracts.
The limitations of smart contract audits
Smart contract audits are essential for the integrity of the blockchain’s core logic. But they focus on the code governing the contract’s operations and overlook the rest of the application, including how it interacts with front-end interfaces and external systems.
This gap showed in several high-profile crypto hacks where the smart contracts themselves were secure, yet the attackers still compromised the platforms through the front end. Security has to extend beyond the smart contract audit.
The role of Web3 penetration testing
Web3 penetration testing looks at the whole application. It examines the external interfaces that interact with the smart contracts and the dApp, in order to find security breaches that could let attackers manipulate dApp interfaces or intercept communications between users and the blockchain.
With web3 penetration testing you can:
- Detect vulnerabilities across the entire application stack.
- Simulate real-world attack scenarios on front-end and third party components.
- Get actionable findings and remediation strategies that go beyond the code of the smart contracts.
Most common front-end attacks in Web3
These are the most prevalent types of attack against the front end of web applications:
- Cross-Site Scripting (XSS). Attackers inject malicious scripts into web pages viewed by other users, exploiting web applications that fail to sanitize input properly. These scripts can steal cookies, session tokens or other sensitive information directly from the browsers of unsuspecting users.
- Cross-Site Request Forgery (CSRF). Unauthorized commands are transmitted from a user that the web application trusts. The attacker tricks the victim into submitting a request via image tags, hidden forms or other deceptive means.
- SQL Injection. Though usually associated with back-end databases, SQL injection can also start from the front end whenever user inputs are improperly sanitized. Attackers can then manipulate SQL queries and potentially access and change sensitive data.
- Remote File Inclusion (RFI). Attackers include remote files through the web application. This can lead to malicious scripts or code executing within the server’s environment, which is a severe security risk.
- Local File Inclusion (LFI). Similar to RFI, but the files included are already present on the server. LFI can be exploited to execute code, traverse directories and access restricted files.
- Broken Authentication. When authentication mechanisms in a web application are implemented improperly, attackers can compromise passwords, keys or session tokens to gain unauthorized access to user accounts.
- Security Misconfiguration. A broad category covering poor security practices such as unnecessary services enabled on the server, outdated software, unnecessary privileges, and unsecured default settings. All of these can lead to unauthorized access and data breaches.
Developers can significantly reduce the risk from these vulnerabilities with regular code reviews, thorough testing and secure coding practices.
HYDN’s approach to blockchain security
HYDN provides blockchain security services including Web3 Penetration Tests, Smart Contract Audits, and Adversarial Simulation. We test both the smart contracts and the environments they run in, against conventional attack vectors and more inventive ones. Our team are Smart Contract Audit and Web3 Penetration Testing experts, and their blockchain experience lets them uncover vulnerabilities a traditional pen tester may miss.
Web3 applications use a range of protocols and interfaces, such as RPC and JSON-RPC, each requiring specialized testing tools and expertise. These protocols handle communication between Web3 apps and the blockchain, and they can also introduce security issues that need thorough examination.
Our methodology for Web3 Penetration Testing is based on our extensive industry experience, best practices in the area of information security, international methodologies, and global methodologies such as PTES and OWASP.
HYDN’s team has over 35 years of cybersecurity and blockchain expertise and is CISSP, CCNP, GCIH, GREM, and GNFA certified. Our team have worked uncovering some of the biggest cybersecurity hacks in history including the 2018 Olympic Destroyer Hack.
Our clients include SushiSwap, Bittrex Global, Sablier, Revert Finance, Telos, SpookySwap, Azuro, Decubate, Swapsicle, and many more.
Conclusion
Attacks on blockchain projects are getting more sophisticated. Smart contract audits are indispensable, but they need to be paired with rigorous web3 penetration testing to cover the rest of the application.
To book a Web3 Penetration Test or Smart Contract Audit, get in touch with our team today.
