Cardano core developer Adam Dean tweeted that the Cardano blockchain testnet was "catastrophically" broken due to a recently discovered vulnerability. The vulnerability was discovered because the staking pool operators were eager to upgrade the main network, and because most SPOs have already upgraded the stage to version 1.35.2, and the version 1.35.3 launched earlier this week is currently unable to carry out blocks. Chain synchronization, which can now only be tested on two new testnets without any block history. Adam Dean said he had urged Input Output CEO Charles Hoskinson to deploy the tools needed for a disaster recovery plan.