As per an official statement on the problem, the IOTA network faced a mainnet incident that started at 2:50 AM UTC on December 29, and was completely settled by 2:50 AM UTC on December 30.
The issue was triggered by an abnormal group of trades that may be categorized as an attack on the network. In its blog post, IOTA Foundation has explained that the issue was sparked by problems at the IOTA Reference Implementation (IRI), which is the open-source Java software that sets out the IOTA covenant that functions on nodes in the public IOTA networks, where customers can remit IOTA tokens among themselves.
In particular, the issue was triggered by an ‘edge case’ in transaction structuring that may be categorized as an attack, IOTA team explained.
The primary cause rests in the fact that the IRI failed to manage an edge case where trades are exchanged between several distinct bundles.
After a trade was marked by IRI as ‘already accounted for’ in a bundle, it got overlooked in the next bundle, causing a junk ledger state from which the node failed to recuperate.
Furthermore, the problem ensured that IOTA’s dedicated network coordinator to end the broadcast of additional milestones.
IOTA’s blog post further clarifies that the Foundation has not come across any similar incidents till date.
The company stressed that the issue was not created by software overhauls or any other elements of the network, but instead happened due to the “absence of transaction processing logic for an unusual set of transactions.”
To resolve the issue, IOTA Foundation rolled out a fresh version of IRI (v1.8.3) on December 30 at 01:58 UTC.
The latest IRI version permitted the coordinator to restart the facility, which later on ensured impressive confirmation rate and solid milestone broadcast rate.
Following the resumption of operations by IOTA at 02:55 UTC, top cryptocurrency exchange Huobi thereafter restarted deposits and withdrawals of IOTA after notifying a brief discontinuation on December 29.
The incident triggered a sell-off of IOTA token, which lost almost 4% in 24 hours to trade at $0.159. Nevertheless, the crypto token has slightly recovered to trade at $0.1602, but still down 0.7% in the last 24 hours.
Notably, last week, BitPay, popular crypto payment processor affirmed that it was unable to serve the clients for more than 3 hours as the firm was working to resolve transaction problems.