In today’s Bitcoin in Brief – Zencash has lost $550,000 in two double-spend transactions following a 51% attack on the network. Developers have taken measures to increase the difficulty of future attacks. The event-ticketing platform Ticketfly is also trying to recover from a hijack. 26 million accounts have been reportedly compromised by a hacker who asked for bitcoin ransom.
Zencash Attacked with Two Double-Spends
The Zencash network has been targeted in a 51% attack on Saturday, June 2. The attacker managed to successfully perform two double-spend transactions while reorganizing the blockchain multiple times and reverting 38 blocks in the longest reorganization.
According to a released statement, the Zencash team received warning of potential attack from a pool operator and took measures to raise the difficulty of future attacks on the network, contacting exchanges to increase confirmation times and recommending a minimum of 100 required confirmations.
The attacker(s) caused the reorganizations of the blockchain between blocks 318165 and 318275. They performed the double-spend attacks in blocks 318204 and 318234 – for 13,000 and 6,600 ZEN, respectively, worth more than $550,000 at current prices.
According to the forensic analysis conducted with the affected exchange, the suspect pool address is znkMXdwwxvPp9jNoSjukAbBHjCShQ8ZaLib and the suspect exchange deposit address is zneDDN3aNebJUnAJ9DoQFys7ZuCKBNRQ115.
At the time of the attack the network’s hashrate was 58MSol/s. Developers believe that the attacker has a private mining operation large enough to conduct the attack and/or supplement with rental hash power. Zencash is a proof of work coin based on the equihash algorithm. All equihash-based networks are exposed to possible influx of new equihash power, the team noted.
Ticketfly Hijacked by Hacker, Trying to Recover
Ticketfly has been reportedly attacked by a hacker who breached its website last week and demanded a ransom in bitcoin to release it. The event-ticketing platform is still trying to recover from the “cyber incident.” “We’re working to bring ticketfly.com back up as soon as possible,” its team said, notifying users that the site is offline.
In correspondence with Motherboard, the supposed hacker claimed to have warned Ticketfly of a vulnerability that allowed him to take control of its database and website. The hijacker asked for 1 bitcoin (BTC) to explain the issue in details but did not receive a reply. According to the publication, after no ransom was paid, the attacker posted the user data online.
“We have learned that some customer information has been compromised as part of the incident, including names, addresses, emails, and phone numbers of Ticketfly fans,” the company admitted without revealing how many accounts have been affected. According the data breach tracking website haveibeenpwned.com, more than 26 million accounts have been compromised, Marketwatch reports.
It’s unclear whether any event tickets have been stolen but a number of promoters, clubs and upcoming shows have been affected by the breach. Ticketfly is owned by San-Francisco based Eventbrite, which bought the platform from Pandora Media in a $200 million deal about a year ago.
Avalon Blockchain Unwinds Acquisition of Crypto Assets
Avalon Blockchain Inc., formerly known as World Mahjong Ltd., has announced it has reached an agreement with Avalon Life S.A. to unwind the acquisition of crypto mining assets and cryptocurrencies it has previously bought. According to a press release, the two sides have not been able to reach a consensus in regards to the holding, conversion, trading, and arbitrage of the acquired digital currencies.
World Mahjong Limited, a provider of online games and entertainment services, decided to enter the crypto sector through the acquisition of crypto mining