Qubic Restarts Blockchain After $1.4M Hack

Layer-1 blockchain Qubic has restarted its network and launched a recovery process after a wallet seed vulnerability allowed an attacker to drain roughly $1.4 million in QU tokens from 1,404 accounts, according to the project's latest update.

Qubic's blockchain explorer shows the network resumed processing ticks at 8:00 pm on Oct. 19, advancing beyond tick 85,371,949, where it was halted on Sunday. The network was halted to prevent further movement of stolen funds after attackers exploited predictable wallet seeds generated by vulnerable wallet software.

Recovery Plan and Claims

Qubic stated that its network validators, known as Computors, approved a recovery plan and that the project launched a claims platform for affected wallet holders. Affected users can check their addresses and submit claims through Qubic's reclaim platform until May 1, 2027.

The vulnerability affected wallet seeds generated using Qubic's web wallet on certain Apple devices and browsers, where an insecure random-number generator produced predictable seeds. Qubic stated it fixed the seed-generation flaw in the latest version of its web wallet.

Wallet Security Update

According to Qubic, users who created wallets with the web wallet before version 4.26.4—released on Oct. 19—should treat them as insecure, even if their funds were untouched. The team advised users to update to web wallet version 4.26.4 or later, create a new wallet, and transfer funds immediately.

Key facts

• Layer-1 blockchain Qubic resumed network operations after being halted on Sunday.
• An attacker drained roughly $1.4 million in QU tokens from 1,404 accounts.
• Network validators approved a recovery plan and opened a claims platform until May 1, 2027.
• The vulnerability stemmed from an insecure random-number generator on certain Apple devices and browsers.
• Qubic released web wallet version 4.26.4 to fix the seed-generation flaw.