During European morning hours, an anonymous individual broadcasted a faulty transaction to the Lisk network. Due to a rare edge-case bug in transaction processing, this transaction was deemed valid and went through the processing steps on each individual node. However, it was an invalid, maliciously customized transaction type that utilised this particular code bug.

For these cases there are security measurements built into Lisk Core in order to prevent the blockchain from continuing and causing forks. For this reason every individual node has temporarily stopped processing new blocks which has resulted in the Lisk network to halt. This is automated and intended behaviour in order to protect our users from any loss of funds.

At this time, there are currently 150 transactions in limbo which occurred after the incident, but were never included into the Lisk blockchain. Our current plan is to not re-broadcast these transactions. The network will continue as if these transactions have never happened – this means no funds are at risk.

In lieu with our commitment to full transparency, we have had similar edge-cases take place 2 or 3 times in the past. In all scenarios, the Lisk blockchain always remained secure, as intended, through the deployment of new Lisk Core versions which fixed such issues and allowed for the Lisk blockchain to continue running as normal.

The fix for this matter has already been discovered and implemented. Today, we will release Lisk Core v.0.9.15 which will resolve the issues and allow for the continual and normal operation of the Lisk network. When this fix is deployed we will ask for all delegates to rebuild their nodes by upgrading to the newest version. Further updates to our community will take place as we progress with resolving this issue.