Ontology Halts Mainnet Block Production Over Potential Security Concern

Ontology stopped producing blocks on its mainnet on Aug. 31 after developers flagged a potential security concern during a daily check, freezing onchain transactions while the network’s technical team and validators conduct an emergency review.

The chain’s official explorer listed block 20,770,893 as the latest block. It was created at 4:24:26 a.m. ET (8:24:26 UTC), providing confirmation of when production stopped.

In its announcement, Ontology did not identify a suspected vulnerability or affected component. It said no confirmed security incident had been found and that there was no indication of asset loss or compromise, based on its current assessment.

In an official post, Ontology described the block-production suspension as a “preventive security measure” rather than a response to confirmed asset loss or an ongoing attack.

Transactions and Exchange Transfers Freeze

Ontology said no onchain transactions will be processed while block production is paused and warned users not to attempt time-sensitive transfers.

Ontology’s bridge interface was still accessible. However, because Ontology is not processing transactions, any bridge transfer requiring an Ontology-side transaction cannot complete until block production resumes.

Upbit separately suspended deposits and withdrawals for ONT, ONG and MBL on the Ontology network. The exchange said trading in those assets would continue and that transfers would reopen only after it confirms deposit-and-withdrawal safety.

Restart Plan Has No Timetable

Ontology said the pause’s duration is undetermined and that block production will not resume until the network has been sufficiently assessed and deemed safe to operate. The review covers the network and related components.

A separate announcement will be issued before or when block production restarts, after the review and any required upgrades are completed, according to the project. The team also told users they do not need to move their ONT, ONG or other onchain assets because of the pause.