Jul 272 mins read

Ethereum's Constantinople Hard Fork Postponed Due to Security Vulnerability

Potential flaw found in one of the software upgrades delayed the fork

Ethereum's Constantinople Hard Fork Postponed Due to Security Vulnerability

The much-anticipated "Constantinople" hard fork of Ethereum was postponed just hours before its planned launch due to the discovery of a security vulnerability that could allow for reentrancy attacks by hackers.

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The Ethereum development team and security community made a joint statement explaining that the potential flaw was found in one of the software upgrades and the decision was made to delay the fork in order to fully assess the risk.

The vulnerability could affect some smart contracts and enable attackers to steal cryptocurrency through repeated transaction requests, while also providing false data on their Ethereum account balance.


Crypto exchanges, miners, and node operators must upgrade to emergency software or revert to previous versions, while most users not operating a full node do not need to take any action.

The new date for the hard fork has not been announced but is expected to be at least a week away.

Overall, it is important to always prioritize security to ensure the safety of the cryptocurrency community.


Ethereum's Constantinople Hard Fork Update

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In preparation for network capacity expansion, Ethereum block rewards are set to be permanently reduced by 33% from 3 Ether to 2 Ether. The hard fork was initially slated for activation on January 16th, 2019, at a block height of 7,080,000. However, as of the time of writing, the last block height processed by the Ethereum network was 7,073,586.

Parity Technologies Manager Afri Schoedon confirmed a significant vulnerability on Reddit and announced that the core development team will hold a teleconference on January 18th, 2019, to decide on additional measures to address the issue. Despite the hard fork delay, Schoedon noted that Constantinople's release would be postponed for at least another week. "We will decide on further measures at the Friday meeting. It will not be launched this week, for now," he said.

The sudden delay in the upgrade caused a decrease in the price of Ether. According to Binance, the price of Ether fell from a 24-hour high of $129.4 to $118 at 10 a.m. on January 16th.

Ether Price Graph

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