We are made to believe that the blockchain is 90% secured from attacks due to decentralized technology, blockchain ledgers and transparency. But, some bad guys, you can call them hackers, tend to take advantage of this 10% chance. There have been a good number of recorded cases of attacks on vulnerable networks in blockchain for instance, 2020 attack on KuCoin, Upbit(2019), Binance(2019)
Therefore, you see that high securedness of the blockchain do not still stop these attackers from testing out their hacks. In this article, I listed five possible techniques by which hackers attack blockchain networks. They include:
1. 51%attack
This is a common technique which results to the hacker accessing more than 50% mining power. It gives them the possibility to rewrite some parts of a blockchain and reset the whole transactions. Cryptos using the PoW(Proof of Work), or those with lower number of miners and nodes, are known to have the highest vulnerability to 51% attacks.
2. Phishing attack
Phishing attacks aim to deceive victims into clicking malicious links and entering personal data. The hackers often disguise as a request from a trusted company and they normally send these fake links directly to the victims' email. Through phishing attacks, these hackers can gain access to personal details, wallet addresses, other important information to access a user's wallet address.
3.Typosquatting
Typosquatting looks almost like phishing. Here the hackers deceive victims into clicking and visiting malicious sites, which bear almost same URL with the site they intended to visit. For instance, while typing in a URL, some careless users spell Google as Gooogle, then hackers who own this misspelt site name can have their way into the user's personal accounts. In blockchain and relating to this, individuals may get tricked into visiting a site disguised as a crypto exchange website. Once they type in their username and password, they unknowingly send the hackers, who are the main website creators, their security information required to access their crypto wallets.
4.Routing attack
Here, hackers intercept data and split the nodes into different partitions thereby creating parallel blockchains. This attack causes serious damage in the network by inputing wrong routing entries in the routing table.
5.DDoS attack
DDoS means "Distributed Denial-of-Service (DDoS) Attack" Here, the hacker bombards a server with internet traffic to prevent users from accessing linked online services and websites. The attacker owns a huge number of nodes which they use to flood the network with bad transactions. Performing a large number of fraudulent transactions restricts the processing of legitimate transactions.
Other techniques of attacks on the Blockchain are; network backlogs, Sybil attack
CONCLUSION:
most cases of phishing attacks, routing or other exchange hacks occur as a result of the User being either ignorant or just carefree, not necessarily the Blockchain technology itself is weak.
So, always be careful with your private keys, and who, where or how you give them, in order to safeguard yourself from falling victim during blockchain attacks.