How an Attacker Emptied 1,404 Qubic Wallets Without Breaking the Blockchain

Qubic (QUBIC) fell 5.2% over the past 24 hours to $0.0000004394, according to BeInCrypto Markets data. The drop came after an attacker drained 1,404 Qubic wallets and validators halted the network.

The total crypto market declined 2.8% over the same window, so QUBIC fell nearly twice as hard. The steeper slide lines up with a security incident the project disclosed on October 18.

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How Weak Seeds Opened 1,404 Wallets

Qubic, the AI-based mining protocol behind last year’s disputed Monero majority claim, said the drain took under two hours. It began at 23:42 UTC on October 17 and ended at 01:26 UTC on October 18.

The attacker took about 2.94 trillion QU, worth roughly $1.29 million at the current price. Qubic traced the theft to wallet seeds generated with insufficient randomness. 

Qubic said seeds created in any browser on an iPhone or iPad before October 18, 2026, were affected. The same applies to seeds made with Safari on a Mac before that date. 

Seeds from the Qubic iOS app created before July 2025 were also affected. A fix in version 4.26.4 stops any new weak seeds from being generated.

“The issue was in seed generation, not in the Qubic protocol itself,” the team said.

Frozen Funds Leave QUBIC Holders Waiting on the Quorum

Qubic’s Computors coordinated a halt at tick 85,371,949. The pause stops all transactions, which keeps the stolen funds locked in place.

Qubic said 87.1% of the drained funds stayed on its network. MEXC received the other 12.9% and froze the receiving account within roughly an hour. Exchanges have also suspended QUBIC deposits and withdrawals.

“Any resolution is a decision for the Computor quorum, under the rules of the network,” the post added.

Meanwhile, Qubic’s Core team is mapping affected identities and drafting proposals for the quorum. 

Cysic Bridge Mint Adds to October’s Exploit Tally

A separate exploit hit Cysic’s cross-chain bridge on October 17, the same day Qubic’s drain began. The Cysic Foundation said an attacker minted 10 million unauthorized Cysic (CYS) tokens on BNB Smart Chain.

Early findings show the attacker breached a database behind the bridge’s services. It then exploited flawed processing logic to forge a mint message.

Cysic blacklisted the recipient address within about 76 minutes, restricting the roughly 2.8 million CYS still held there. The bridge remains closed, and Cysic says no existing user assets were stolen. 

The team has not yet quantified the damage, noting that the minted amount does not equal the final dollar loss.

The two incidents add to 11 exploits DefiLlama has recorded so far in October. Those account for about $6.2 million in disclosed losses. The largest was a $3.8 million bridge logic flaw at NEAR Intents on October 1.

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