Qubic Halts Network After Wallet Seed Exploit Drains 1,404 Wallets

Qubic, a layer-1 blockchain, halted its network after an attacker drained about 1,404 wallets of roughly 2.94 trillion QU, worth around $1.3–1.4 million, in a window that ran from late on October 17 to early on October 18, 2026 (UTC). The project says the flaw sat in its wallet software rather than in the blockchain protocol, according to crypto.news.

What happened

The theft took place in under two hours. The attacker went after wallets whose recovery seeds had been generated with too little randomness, which made the matching private keys possible to guess and check against funded addresses. Qubic says the problem was in the tool that creates wallet seeds, not in how the chain itself validates transactions.

Wallets at risk were those created through a browser on an iPhone or iPad, through Safari on a Mac before October 18, and through older releases of the Qubic iOS app. The seed generator relied on a standard random-number function that was never meant to protect cryptographic secrets. A patched web wallet, version 4.26.4, now uses a cryptographically secure source instead.

The network halt and frozen funds

To stop the stolen tokens from moving further, validators paused the network at tick 85,371,949. Reports put about 87% of the stolen amount, near 2.56 trillion QU, still on the Qubic chain when it stopped, which leaves those coins frozen in place.

The remaining 13% or so, about 379 billion QU, had already reached the exchange MEXC. The exchange froze the receiving account. Exchanges then suspended QUBIC deposits and withdrawals, so holders cannot move the token until the chain restarts.

• Wallets affected: 1,404
• Amount taken: about 2.94 trillion QU
• Still on-chain and frozen: about 87%
• Sent to MEXC: about 13%, with the account frozen

Why it matters

Seed-generation weaknesses are a recurring problem in crypto. A recovery phrase is only as safe as the randomness behind it, and a user cannot see that from the outside. Wallets made with the flawed code before the fix may still carry risk, which is why the patched wallet release matters for anyone who used the affected apps.

The response also raises a governance question. A halt that freezes most of the stolen funds shows how much influence a small group of network operators can have over user assets. Qubic calls these operators Computors, and they are expected to vote on how any recovery works.

Market reaction

The incident has stayed largely contained to the token rather than spreading across the wider market. CryptoWave data shows Qubic at about $0.0000004636, up 2.22% over 24 hours, with a market capitalisation near $66.6 million and a rank of #383. Volume is thin at roughly $0.7 million over the same period, so prices can move sharply on small orders. For comparison, Bitcoin trades near $82,000, and the market heatmap shows the broader market little changed.

What to watch next

• Recovery vote: the Computors are expected to vote on recovery proposals and on whether victims receive restitution. No plan has been approved yet.
• Restart: no date has been announced for the network to resume, and exchange deposits and withdrawals remain suspended until it does.
• Technical report: Qubic has said it will publish a full report once the recovery plan is settled.
• The MEXC portion: it is not yet clear whether the frozen funds on the exchange will be returned.

Readers can follow lower-cap tokens that move on events like this with the CryptoWave screener. Qubic has not confirmed that any stolen tokens have been returned to their owners, and the details above may change as the project releases more information.