The blockchain technology has been praised for many reasons. However, similar to all things, it isn’t a perfect platform and is still vulnerable to hackers.

And these hackers have struck again, with their skill-set aimed at Verge, a privacy-centered crypto company. The Next Web reported that the criminals managed to haul in over $1.7 million in the span of four hours.

On May 22, the company tweeted that some of their mining pools were under DDOS attack and they’re finding a way to resolve it. It can also be remembered that Verge also suffered hacking incidents in the early parts of April resulting in a 25 percent drop of XVG value.

The method used by the hackers exploited vulnerabilities present in Verge’s platform. Here’s how it went.

To start, know that the possibility of carrying a real mark of all existing blocks in a certain blockchain isn’t conceivable because the data being sent between nodes isn’t instantaneous. As such, the network then permits some irregularities between blocks whose timestamp doesn’t extend on a certain timespan. That timespan for XVG is 2 hours.

The hackers exploited this by tampering with the block submissions. This, in turn, created confusion to the platform’s mining adjustment protocol. Since not enough blocks are being submitted, the system lowered the mining difficulty trying to alleviate the problem not knowing that it’s actually being attacked. By the end of it, the difficulty was lowered by 99 percent resulting in block submissions every second.

The hacker reportedly hacked one of the five of the consensus algorithm used by Verge, which is Scrypt. This means that the attack didn’t lower the difficulty of all five algorithms, but rather decreased only one. The hackers only then have to compete with those mining Scrypt, while rendering the hash-power used by the other four for security measures effectively useless.

During the attack, the hackers managed to take over the network by 51 percent. While this incident was unfortunate for Verge, experts are blaming the company itself because it didn’t employ a more rigid security network following the attack on April, calling the intervention implemented as good as a Band-Aid. Moreover, the strategy used during the April hack is closely similar to the one recently used by the hackers.