Qubic Halts Its Network After Attacker Drains 1,404 Wallets Through Weak Seeds

Qubic, a crypto network that markets itself for AI computing, has stopped processing transactions after an attacker emptied 1,404 user wallets. The attacker exploited wallet seeds that were “generated with insufficient randomness”, the project said in an official thread on X. Seeds created on iPhones, iPads and in Safari on Macs are among those affected.

What Qubic says happened

“Between 23:42 UTC on 17 October and 01:26 UTC on 18 October, an attacker drained 1,404 Qubic wallets, totalling around 2.94 trillion QU,” Qubic posted on 18 October at 12:29 UTC (13:29 UK time). In UK time, the attack ran from 00:42 to 02:26 on Sunday morning, a window of 1 hour and 44 minutes by TSN’s count.

“Some wallet seeds were generated with insufficient randomness, making them weaker than they should be,” Qubic said. “The attacker exploited this to access the affected wallets.” A seed is the secret phrase or code that controls a crypto wallet. If it is not random enough, an attacker can guess it.

Qubic stressed that its blockchain itself was not broken. “The issue was in seed generation, not in the Qubic protocol itself,” it said.

Which wallets are affected

According to Qubic, seeds are affected if they were created:

• “On an iPhone or iPad, in any browser, before 18 October 2026”
• “On a Mac using Safari, before 18 October 2026”
• “In the Qubic iOS app, before July 2025”

That covers more than old devices. Any seed made on an iPhone or iPad browser, or in Safari on a Mac, up to the day of the attack is on the list. Qubic has not said whether every seed in these groups was weak, or only some.

The network is frozen

Qubic’s network is run by operators called Computors. “Computors coordinated a protective halt of the network at tick 85,371,949,” Qubic said. “No transactions are processing, so the drained funds cannot be moved or sold while this is resolved.”

Most of the money did not get far. “87.1% of the drained funds never left the Qubic network and remain frozen in place,” Qubic said. “The remaining 12.9% was sent to MEXC, whose team froze the receiving account within about an hour.” By TSN’s arithmetic, that is roughly 2.56 trillion QU still on the network and about 379 billion QU sent to MEXC.

Qubic added that “Exchanges have been notified and have suspended QUBIC deposits and withdrawals.” MEXC’s announcement says: “As requested by the Qubic (QUBIC) project team, MEXC has suspended QUBIC deposits and withdrawals.” Crypto Briefing reports that Bitget has also suspended QUBIC deposits and withdrawals. TSN has not seen a Bitget notice.

How much was taken

Qubic has not given a dollar figure. The Defiant puts the loss at $1.3 million, and Crypto Briefing describes the 2.94 trillion QU as “worth approximately $1.3 million at the time”. Those are the outlets’ estimates.

The fix, and what happens next

“Seed generation has been corrected in version 4.26.4,” Qubic said. “No new weak seeds can be created.”

No compensation has been promised. “Any resolution is a decision for the Computor quorum, under the rules of the network,” Qubic said. It said its core team is identifying every affected identity and preparing options for the quorum, and that a community poll is open on Discord “to give the Computors a clear view of where the community stands”.

“A full technical report will follow once recovery is settled,” Qubic said. It has not said when the network will restart.

Crypto Briefing notes that this is not the first incident around Qubic this year, reporting that the Vottun Bridge connected to Qubic was exploited in August 2026.

What to do if you hold QU

• Check where your seed came from. If you created it in a browser on an iPhone or iPad, in Safari on a Mac before 18 October 2026, or in the Qubic iOS app before July 2025, it is on Qubic’s affected list.
• Report losses. Qubic asks affected users to file a report with the police or cybercrime authorities in their country, including the wallet ID, the amount lost and the transaction link from the Qubic explorer. “Formal reports help exchanges keep funds frozen,” it said.
• Beware of recovery scams. “Nobody from Qubic will ever message you first, ask for your seed, or offer recovery services for a fee,” Qubic warned. Never share your seed with anyone. Qubic asks users to report any such messages.
• Wait for official updates. Any decision on recovering funds rests with the Computor quorum. Follow Qubic’s official channels rather than direct messages.

What this means

• An attacker drained 1,404 Qubic wallets, about 2.94 trillion QU, by exploiting weakly generated seeds. Qubic says the flaw was in seed generation, not in the protocol.
• The network has been halted. Qubic says 87.1% of the funds never left its network, and MEXC froze the account holding the rest.
• No compensation has been promised. The Computor quorum will decide, and a full technical report is due later.

Sources

• Qubic on X: security incident update thread, 18 October 2026
• MEXC: Suspension of QUBIC Deposits and Withdrawals
• The Defiant: Qubic Halts Network After $1.3 Million Wallet Drain
• Crypto Briefing: Qubic halts mainnet after wallet drain empties 1,404 accounts

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