Litecoin’s official account confirmed on Saturday afternoon that a zero-day bug triggered a denial-of-service attack against major mining pools, leading to a 13-block chain reorganization that reversed invalid transactions before they could settle on the main chain.
Key Takeaways:
- Litecoin confirmed a zero-day bug hit major mining pools on April 25, 2026, enabling invalid MWEB transactions via non-updated nodes.
- A 13-block reorg reversed the invalid transactions; Litecoin states all valid transactions are safe and the bug is fully patched.
- NEAR Intents had reported $600K in exposure, but actual losses may be lower now that Litecoin confirms the invalid transactions were wiped.
Litecoin Reorg Issues
According to the Litecoin team, non-updated mining nodes processed an invalid MWEB transaction that allowed coins to be pegged out to third-party decentralized exchange ( DEX) platforms. The bug gave attackers a path to push fraudulent transactions through nodes that had not applied recent updates.
The 13-block reorg was the network’s response to that exploit. It reversed the invalid transactions and prevented them from being included in the main chain. The Litecoin team confirmed that all valid transactions during that period remain unaffected.
The team insists the bug has since been fully patched. The Litecoin network is operating normally as of the team’s statement posted at 4:22 p.m. ET on April 25.
Aurora Labs CEO Alex Shevchenko and onchain analyst Zacodil had flagged the reorg earlier in the day, with observers initially interpreting the 13-block reorganization as a classic 51% attack. Onchain timestamps showed those blocks took more than three hours to generate, compared to the normal target of roughly 32 minutes for 13 blocks at Litecoin’s 2.5-minute block time.
The official Litecoin statement reframes what happened. The reorg was allegedly not attackers successfully rewriting history for profit. It was the network correcting a bug-driven exploit by discarding the invalid chain.
NEAR Intents had originally reported approximately $600,000 in exposure, saying its team would cover any user losses. With Litecoin confirming the invalid transactions were reversed and wiped from the main chain, the actual settled losses may be significantly lower than initially reported. NEAR Intents has not yet issued a follow-up statement addressing the updated picture.
Other cross-chain protocols that accept LTC and paused activity in response to the incident are also expected to reassess their exposure now that the Litecoin team has clarified the sequence of events.
To many, the incident highlights a real vulnerability in proof-of-work networks that run nodes on older software versions. Non-updated nodes processed a transaction they should have rejected, which gave the MWEB exploit its opening.
“This isn’t an isolated incident. There have been many of these rollback-and-double-spend attacks against Proof-of-Work-alone blockchains both years ago and recently, including recently against Monero and Grin,” Zcash founder Zooko Wilcox wrote on Saturday.
This story is still developing.