Enhancing the Security in Blockchain | Risk Crew

The Emergence of Blockchain Technology 

How did we arrive at blockchain technology? Let’s start from the beginning. The internet, which has been in existence for over 60 years, is built on the TCP/IP and OSI model stack. Originally designed for information sharing through the client-server model, the internet has evolved into a powerful technology that blurs the line between truth and illusion.  

When it comes to networks, organisations prefer client-server setups. They’re reliable, stable and give total control over data. Also, clients manage their local resources while servers handle shared resources like hardware, networks and databases.  

But hold on, things are getting trickier with cyber-attacks. So, organisations are on a quest for new ways to protect themselves. This has led to the emergence of blockchain technology. Unlike the traditional centralised system that relies on a central authority, blockchain is designed to be decentralised. It ensures security through an open and distributed chronological ledger that securely records transactions of any value or asset.

Different types of blockchains exist: 

• Public blockchain: These are large, open-source, distributed networks accessible to anyone. 
• Permissioned blockchain: These are also large and distributed networks but have strict membership rules and permissions. They aim to prevent unauthorised access to sensitive information and prohibit changes to the blockchain. 
• Private blockchains: These are smaller, closed, and heavily centralised networks that typically do not utilise a token. They employ different methods for memberships and have various user roles within the blockchain network. 

Blockchain Benefits and Risks 

There are numerous benefits with blockchain technology as it’s a powerful tool for various applications, providing secure and transparent solutions for industries ranging from finance and supply chain management to healthcare and governance. Some top benefits include: 

• Decentralisation: Blockchains are highly decentralised and distributed, eliminating the reliance on a central entity. This reduces the risk of data being controlled or manipulated by a single authority. Every node in the network maintains a copy of the latest ledger, ensuring redundancy and avoiding a single point of failure. Computational trust ensures that no node or ledger copy is more trusted than others. 
• Immutability: Once a transaction, asset, or value is recorded on the blockchain by a node, it becomes immutable. It cannot be altered or removed, providing a high level of data integrity and tamper resistance. 
• Process Integrity: Blockchain systems follow predefined rules set by the developing community. Users can trust that transactions will adhere to these rules, ensuring transparency and fairness within the network. 

• Openness: Many blockchains are open source and permissionless, allowing anyone to participate in the network. This openness fosters inclusivity and encourages innovation. Users can even create their variations of the blockchain through hard or soft forks. 
• Transparency: Blockchain systems provide transparency as every transaction, whether old or new, is visible to all participants with access to the system. This visibility helps verify the authenticity of transactions, preventing counterfeiting and fraudulent activities. 
• Fault Tolerance: Blockchains are designed to be fault tolerant. Even if a node fails, the network can continue to function seamlessly. There are no mission-critical nodes, ensuring the system’s resilience and availability. 
• Programmability: Blockchains utilise smart contracts to develop and execute business logic automatically on top of the distributed ledger. This programmability allows for the creation of complex decentralised applications and enables automation within the blockchain ecosystem. 

While blockchain technology offers numerous benefits, it is not immune to cyber-attacks and fraud. Hackers with in-depth knowledge, particularly regarding smart contracts, have been exploiting vulnerabilities and siphoning off millions of dollars over the years. 

Common Methods Used by Hackers to Compromise Blockchain Security

Understanding the vulnerabilities associated with blockchain and implementing robust security measures is crucial to ensure the integrity and safety of blockchain systems and protect against potential attacks. Here are some common attacks hackers use: 

• Distributed Denial of Service (DDoS) Attacks: Blockchain technology, despite its peer-to-peer nature, remains vulnerable to DDoS attacks. Large mining pools, enterprises, and currency exchange services are prime targets due to the potential for substantial financial gains. 

• Network Node Vulnerability: Sometimes, the design of the blockchain network itself can be flawed, creating weak spots. It’s like a chink in the armour, and if your infrastructure isn’t up to snuff, trouble awaits. The underlying infrastructure must be aligned with the blockchain’s requirements, as conflicts with an organisation’s network security protocols or insufficient bandwidth can create vulnerabilities. 
• 51% Attacks: Imagine a hacker gaining control over more than half of the blockchain’s power. It’s like holding all the cards and pulling off double-spending tricks left and right. This enables manipulation of the blockchain, including double-spending attacks, by acquiring most of the computational power through various means. 
• Eclipse Attacks: In an eclipse attack, the attacker takes control of all connections of a node within the network. By manipulating the node’s view of the distributed ledger and network operations, the attacker can carry out double-spending attacks, Denial-of-Service attacks, or unauthorised use of the node’s computational resources. 
• Replay Attacks: Remember digital signatures? Well, attackers can pull off a replay attack by resubmitting legit transactions as new ones, exploiting the acceptance of the original transaction’s valid digital signature. This allows the attacker to potentially benefit by receiving payment twice. 
• Routing Attacks: In this case, the hackers’ attacks target the communication network used by the blockchain, enabling an attacker to control communication between different sets of nodes. By partitioning the network, they divide and conquer, making mischief galore – facilitating 51% of attacks, Denial of Service attacks, and double-spending attacks. 

• Sybil Attacks: Picture an attacker creating multiple accounts to wreak havoc on the blockchain to gain control and execute attacks such as eclipse attacks, routing attacks, and manipulation of consensus algorithms. Implementing access controls and using permissioned or private blockchains can mitigate the risk of Sybil attacks. 
• Shared Vulnerabilities: If a hacker gets hold of a node’s private key, they have the keys to the kingdom. Failure to update blockchain software can lead to network splits, weakening security. 
• Misconfigured Membership Service Providers: Permissioned blockchains have membership service providers that can be compromised. It’s like a weak link in the chain. Protecting MSPs against DDoS attacks and ensuring their security is crucial. 
• Insecure API Connections: APIs that interact with the blockchain need to be designed securely to prevent compromised or misconfigured applications from jeopardising the integrity of the blockchain. Implementing access control measures and input sanitisation is essential. 
• API Penetration Tests: It’s like a check-up for blockchain APIs. Testing the interaction with the blockchain ecosystem through APIs to validate the correctness and proper operation of requests and responses. 

• Consensus Mechanism Attack: Attacking the consensus protocol can disrupt or manipulate the blockchain network, compromising its integrity and security. 
• Specific Attacks on Proof of Stake (PoS) and Proof of Work (PoW) Blockchains: Attacks such as 51% attacks, alternate history attacks, Finney attacks, race attacks, and Vector67 attacks exploit vulnerabilities in the consensus mechanisms to perform double spending, manipulate transactions, or gain control. 
• Smart Contract Vulnerabilities: Smart contracts can have various vulnerabilities that attackers exploit, including EVM bytecode vulnerabilities, re-entrance, access control issues, arithmetic overflow and underflow, unchecked return value handling, denial of service (DoS), bad randomness, race conditions, timestamp dependencies, short address vulnerabilities, and many others. 

Blockchain Risk Management 

• To effectively combat the vulnerabilities and risks mentioned above, it is crucial to engage in comprehensive security advisory and risks assessments. Risk Crew experts recommend following an approach that includes: 

  • Security Advisory: Gain valuable insights and tailored recommendations through in-depth security advisory services, assessing your blockchain infrastructure for vulnerabilities. 
  • Vulnerability Assessments: Identify weaknesses and misconfigurations with thorough assessments of your blockchain networks, including nodes, smart contracts, and APIs.  
  • Penetration Testing: Simulate real-world attacks to uncover entry points for hackers and assess the effectiveness of your security controls. Receive comprehensive reports with actionable recommendations. 
  • Smart Contract Audits: Ensure the security and integrity of your smart contracts by leveraging expertise in blockchain technology. Audits help to identify vulnerabilities and logical flaws, safeguarding against financial losses. 
  • Incident Response Planning: Develop robust incident response plans tailored to blockchain security incidents.  
  • Security Awareness Training: Educate your employees, developers, and administrators about blockchain risks and best practices through comprehensive security awareness training. Foster a security-conscious culture. 
  • Ongoing Security Monitoring: Implement continuous security monitoring solutions to proactively detect and respond to potential threats. Stay ahead of attackers with real-time analysis and anomaly detection. 

Stay Blockchain Secure 

In conclusion, ensuring robust blockchain security is of paramount importance in today’s digital landscape. As blockchain technology continues to revolutionise various industries, protecting the integrity, confidentiality, and availability of data and transactions becomes crucial. By implementing comprehensive security measures such as strong access controls, encryption, regular vulnerability assessments, and smart contract audits, organisations can mitigate the risks posed by evolving cyber threats. 

Want to learn more? Speak to one of our consultants today about blockchain security and risk management.