If we peep into the security landscapes today, we will find many changing scenarios now and then. What remains constant here is the promising aspects of blockchain technology that have possibly created a lot of buzzes.
Within this domain, the smart contract is the core, widening the horizons of blockchain technology. Nowadays, we can easily find its applications in different sectors like healthcare, business process management, IoT, digital identity, supply chain, etc.
The combination of blockchain technology and smart contracts is doing wonders for users, making this sphere a lot smoother and safer for transactions, even without a trusted central authority. Though there has been a forward progression toward utilizing this combo, there is also a need for more cautiously checking smart contract security.
Being an innovative technology, smart contracts’ role in different domains like digital asset exchange, intellectual property, supply chains, and crowdfunding is inevitable. Sadly, there have also been so many security issues in smart contracts that are reported till now, resulting in substantial fund loss. These issues have created havoc for the users in this decentralized and immutable environment.
As a result, a wide range of solutions is becoming available to identify and fix security flaws. On a worldwide level, it is essential to recognize and address the rising smart contract security issues.
When developing smart contracts, a minute error can significantly leak funds! Therefore, security becomes something that we should pay attention to. This blog aims to give you insight into the security recommendations you need to keep in mind while developing your smart contracts. So, let us get started.
What factors are responsible for reducing the security of smart contracts?
For every smart contract, security is prime. Developers need to understand the weakest spots in blockchain networks to make their contracts less susceptible to a wide range of security flaws and malicious hacks.
Several factors, like protocol bugs, programming, and compiler errors, must be considered when securing smart contracts. Other than these, these are some factors that affect smart contract security.
- Virtual Machines
These are only a few of the numerous sources of severe mistakes and security problems. For instance, the Ethereum Virtual Machine (EVM) is prone to many errors, from access control problems to immutable flaws brought on by programming faults in the contract code.
- Source Code
The development of smart contracts, several of them have their programming languages. Nowadays, several blockchain systems allow smart contracts, including Ethereum, Hyperledger, EOS, Stellar, and Tezos. These systems employ different programming languages, tokens, and consensus techniques. Their discrepancies lead to a variety of security problems and vulnerabilities. The vulnerabilities could not be discovered, resulting in enormous losses in different blockchains.
Let us briefly discuss the types of security flaws in blockchains and see their consequences.
|Types of Smart Contract Platforms||Security Issues||Consequences|
|Reentrancy Attack||It happens because an external contract repeatedly calls a function before the execution of an existing contract is finished. During execution, the contract’s status is altered. The DAO attack is one example of a security concern in this area.|
|Ethereum||Denial of Service Attacks||Attackers can repeatedly utilise the bid() method in an auction contract to stop other users from submitting bids.|
|Numerical Overflow||EOS smart contracts may not verify the limits, making them susceptible to overflows, especially when executing arithmetic operations. The values could overflow as a result, which would result in the loss of users’ assets.|
|Integer Overflow||When an integer variable holds a value greater than its predetermined limit, it is said to be in an overflow state. It is the flaw that hackers used to compromise the ERC currencies during the batchOverflow attack. Attackers generated an excessive amount of tokens by taking advantage of certain ERC20 contracts.|
|EOS||Remote Code Execution||The global blockchain network might be harmed by a function library’s incorrect array limits check. Due to this flaw, attackers are able to take control of the node by sending data to arbitrary locations in memory using rogue smart contracts with invalid values.|
|RAM Exploit||RAM attack is another security vulnerability in the EOS network. A malicious smart contract is created by the attackers to occupy and block RAM and stop any further activities.|
|Tezos||Callback Authorization Bypass attack||The message-passing architecture of Tezos precludes contracts from accessing an external call’s return value. Access control problems arise when employing a callback function since there is no built-in mitigation.|
Hopefully, this table clarifies all your doubts regarding this topic. Now, let us see the practices we can use to secure our smart contracts.
The best practices for securing smart contracts
Whatever blockchain platform, there is no such platform that does not have any vulnerability present in it. Yet, it is even possible to get rid of them in the very early development stage. The most effective way to eliminate them is by undertaking the best practices so that you don’t have any vulnerability in your contract.
Let us give the best practices for each blockchain platform.
Solidity Smart Contracts
When handling smart solidity contracts, these are the best practices you must undertake to make them secure.
- Keep funds in a contract.
- Remember to use fallback functions and race conditions.
- Make it a habit to label functions and state variables.
- Use events to track activities in the contract
- To check, use modifiers
- Prevent rounding the integer division
- Tradeoffs between interfaces and abstract contracts
Ethereum Smart Contract Security
It is a well-known fact that Ethereum is the most widely used blockchain platform. Hence, one needs to be extra cautious while developing smart contracts on Ethereum. Follow these practices to make it secure.
- Mark untrusted contracts
- Manage function codes that consist of conditions, interactions, and actions.
- Handle errors in external calls
- Never use delegatecall functions to untrusted code
- Pull external calls rather than pushing them
EOS Smart Contract Security
The actions on the mainnet must be observed by the EOS platform’s smart contracts. Inadequate testing might result in deadly defects that have disastrous implications for the entire network. The following principles for smart contract security must be considered and implemented while working on EOS platforms.
- Evaluate the numerical overflow
- Use killswitch
- Analyze authorization
- Set the limit transfer rate
- Use assumptions
- Generate true random numbers
Tezos Smart Contract Security
The functionality and accuracy of the smart contracts on the Tezos platform are exceptional. Tezos provides verification, which guarantees the accuracy of smart contract codes and increases their dependability and security.
Some of the advantages of Tezos are:
- It has specialized tools to create business-oriented Dapps
- There is no need to rely on compilers to convert the program into bytecodes that cannot be read.
- It gives the ability to analyze the smart contract code
Coming to the best security practices for Tezos, these are some of the practices that you must follow.
- Ensure that there are no repetitive messages
- Prevent batch operations
- Add owners to smart contracts.
- Do not store or transfer private data that is not secure.
- Add role-based access control.
In comparison to conventional legal contracts, smart contracts are a well-known solution with several advantages in terms of trust, accuracy, and cost-efficiency. Smart contracts share many hidden flaws and coding faults with other applications, ultimately compromising security. The sort of blockchain network you deal with, the programming language and platform you employ, and the type of testing you conduct before releasing the final version are all crucial considerations regarding smart contracts security.