Research On Key Technologies Of APT Attack And Defense Based On Blockchain

With the development and continuous application of blockchain technology,many services use blockchain as data storage,including many large organizations and government systems.Moreover,blockchain-related development plans are included in China’s "14th Five-Year Plan".Therefore,blockchain has broad application prospects.Blockchain is a distributed storage system with features such as decentralization,which has many application scenarios deployed across networks.However,blockchain systems are more vulnerable to advanced cyber-attacks due to the storage of large amounts of critical data.Furthermore,the blockchain system applied across the network will lead to blurring the network security boundary and provide the preconditions for the attacker to execute advanced persistent threat operations,causing a considerable security threat to the related systems and networks using the blockchain.Therefore,many researchers focus on the security of blockchain systems.However,most of the research on security protection is mainly focused on information security transmission,which lacks the protection of external security caused by the blockchain framework.To improve the security of blockchain,the work of this thesis is as follows:(1)To show the possible security risks of the blockchain,this thesis first studies the weak module related to the blockchain by extracting the key step of the advanced persistent threat attack.Subsequently,this thesis proposes using a series of smart contracts in the blockchain to show the threat,including remote command execution,remote resource access,multi-level attack chain,and non-blockchain larger data transmission.(2)To solve the risks of advanced persistent threats in various network systems,a fusion protection technology of moving target defense and access control is proposed,which can enhance security and mitigate the threat of advanced persistent threat attacks to other systems.In particular,the fusion protection technology on the IPv6 network significantly improves defense efficiency compared to the IPv4 network,which can achieve almost 100% security protection at most.(3)To reduce the security risks existing in the current blockchain system,this thesis proposes using the software-defined network-based fusion protection technology of moving target defense and access control to protect the blockchain system.The fusion protection technology provides a secure closed-loop exchange scheme for the data transmission of the blockchain system in the public network.At the same time,the fusion protection technology does not require modifying the existing network and blockchain system,which can easily use in unmanageable networks.