Stellar experienced a ledger fork due to weaknesses in its Ripple-based consensus algorithm. The network temporarily switched to a single validator node and is prioritizing development of a new provably correct consensus system to prevent future forks and double-spend risks.
The Stellar network experienced a ledger fork when nodes disagreed on the ledger state, causing a rollback of several hours of transactions. The incident revealed fundamental limitations of the Ripple/Stellar consensus algorithm, which prioritizes availability over safety and cannot guarantee all nodes agree on the ledger. With 140,000 active accounts, the network exceeded the algorithm's safe operating scale of approximately 120,000 accounts. In response, Stellar temporarily deployed a single validator node to prevent further forks and is accelerating development of a new consensus algorithm led by Stanford professor David Mazières that will be provably correct and prioritize safety over guaranteed termination.
