INFO51% Attack to Callisto.Network - February/2019On Saturday the 23rd, a series of attacks began, starting with a failed attempt that destabilized the network, causing that some of the nodes from mining pools became outdated/desynced from the main chain. The following days Callisto Network got more elaborate attacks trying to apply the "double spending exploit" on exchanges like Stex and HitBTC, mostly unsuccessfully.
On Monday the 24th we kept in contact with exchanges and pools to reduce the losses that future attacks might generate. The initial measure was to temporarily close HitBTC wallet and increase the number of confirmations required by Stex.
On Tuesday the 26th a new attack occurred. We took the decision to move forward in the implementation of PirlGuard to counteract the 51% attacks. Initially, the announcement stipulated a hard fork with PirlGuard in the block 2,160,000 to give us some time to work on it and test it. That same day at the UTC-5 time slot, the solution was already coded by our team and it was ready to be deployed with the implementation of Pirl Guard source code against 51% attacks and with the last stable version of Geth. After the implementation, Yohan Graterol, CEO of Callisto got in touch with EPool manager who agreed to perform simulated attacks in a private network in order to test the code. During the whole process of implementation and testing, we were in constant communication with Pirl's Founder.
The founder of EPool ran differents 51% attacks tests on the latest go-Callisto version and this was the last result:
https://media.discordapp.net/attachments/550198213152473088/550273619482116126/Screenshot_2019-02-27_05-09-50.pngFollowing these tests, it was requested a code revision by Callisto from Pirl team to ensure that everything was implemented correctly.
On Wednesday the 27th before 19:00 UTC, the binaries were released for all platforms:
https://github.com/EthereumCommonwealth/go-callisto/releases/tag/1.0.6, in this release the hard fork was moved from block 2,160,000 to block 2,135,000. Plenty of help, hard work and coordination made this possible.
Today, the 28th at 15:58:40 UTC, block 2135000 (
https://explorer2.callisto.network/block/2135000) was mined, successfully activating the 51% attack protection.
Throughout the process, the exchanges and most of the mining pools provided help and understanding that allowed a hard fork process like this to take place in less than 48 hours.
Special thanks to Stex, HitBTC, Epool, MaxhashPool, CLOPool, Callisto community and to all the Callisto staff.
Thanks to Trust, Coinomi and Guarda wallet for the support.
Stex will reopen the wallets tomorrow followed up by HitBTC, this way deposit and withdraws will be resumed.
The 28th was going to be a great day for Callisto. And it was. But not in the way or with the outcome we all expected.
We all were expecting a listing. But we got a hard fork that protects the network from malicious people trying to do some damage. In long term, this is more important than any listing.
The new listing will be delayed since the exchange needs to run some test again with the new fork before launching CLO coin, especially if it was getting 51% attacks during the last week. This delay won't be eternal. We hope to deliver you a final listing date within next week.