Qubic halted blockchain operations at tick 85,371,949 on Sunday, October 18, 2026, after attackers exploited a vulnerability in the process used to generate wallet seeds, stealing 2.94 trillion QUBIC tokens valued at approximately $1.4 million. The network remained paused at the time of reporting as the project worked to identify affected wallets and determine how the stolen assets could be recovered. A halted blockchain cannot process new transactions, leaving on-chain activity suspended until operations resume.

The incident exposed weaknesses in the mechanism used to create wallet seeds, which are essential for securing access to cryptocurrency holdings. According to Qubic, the flaw affected seeds generated through browsers on iPhones and iPads, Safari on Mac computers before October 18, 2026, and the Qubic iOS application before July 2025.

Qubic has frozen 87.1% of the stolen funds on its own network, while the remaining 12.9% was frozen at cryptocurrency exchange MEXC, limiting the attackers' ability to move the assets. The coordinated freezes mean most of the stolen balance cannot currently be moved by the attackers. The project has not announced a date for resuming blockchain operations; its immediate priorities are securing affected wallets, assessing recovery options, and preventing further exploitation.

Qubic Replaces Vulnerable Random Number Generator

Qubic said it corrected the seed-generation flaw in the latest version of its web wallet. A GitHub commit associated with version 4.26.4 shows that the project replaced JavaScript's Math.random() function with crypto.getRandomValues() during seed creation. Committing the fix publicly on GitHub makes the change independently reviewable. The fix applies to newly generated seeds, while wallets created earlier through the affected channels fall under the review now underway.

The change is significant because wallet security depends on generating unpredictable cryptographic values. Math.random() is designed for general-purpose pseudorandom number generation rather than cryptographic security, making it unsuitable for producing sensitive wallet credentials. By contrast, crypto.getRandomValues() provides access to cryptographically secure random values supported by modern browsers.

If attackers can predict or reproduce wallet seed material, they may be able to derive access credentials and take control of the associated funds. Replacing the vulnerable random-number generator with a cryptographically secure method addresses the identified weakness and is intended to strengthen protection for newly generated wallets. Users whose wallets were created through the affected platforms and timeframes may need to assess whether their credentials remain secure.

Network Computors to Decide Recovery Plan

Qubic's core team is identifying affected wallets and preparing potential recovery measures for a future vote by the network's Computors, which participate in the blockchain's decision-making process. The project addressed the incident publicly on X:

What happened: Some wallet seeds were generated with insufficient randomness, making them weaker than they should be. The attacker exploited this to access the affected wallets. The issue was in seed generation, not in the Qubic protocol itself.

— Qubic (@Qubic), October 18, 2026

The vote is expected to determine how the frozen funds should be handled. However, the project has not yet disclosed the available recovery options or established a timeline for the decision. Until a plan is approved, frozen balances remain immobilized on the network and at the exchange. Qubic also plans to publish a comprehensive technical report after a recovery plan has been finalized; the report is expected to provide further details about the vulnerability and the incident's consequences.

The suspension underscores the operational challenges blockchain projects face when responding to security breaches involving wallet credentials and substantial token transfers. Although freezing funds can prevent some transactions from progressing, recovering stolen assets may require additional technical measures and network-level decisions.

Exploit Highlights Broader Cryptocurrency Security Risks

Qubic, whose token trades under the ticker QUBIC, operates as a fee-free layer-1 blockchain supporting transactions and smart contracts. Its consensus model, known as Useful Proof of Work, is designed to redirect mining resources toward artificial intelligence training. The project's token had a market capitalization of approximately $62.6 million at the time of reporting, according to CoinGecko, making the value of the stolen tokens equal to a little over 2% of that figure.

The attack also reflects broader concerns about cryptocurrency theft arising from weaknesses in wallet security. According to AMLBot's 2026 investigations report, which covered 250 investigations opened since the beginning of the year, hacks and exploits accounted for 19% of cryptocurrency crime cases in the third quarter but represented 40% of reported losses — a gap showing that such incidents, while a minority of cases, carry a disproportionate share of financial damage.

The Qubic incident demonstrates how a vulnerability in a foundational security component can expose digital assets even when the underlying blockchain is not the direct source of the weakness. The network's next steps will depend on the recovery vote, the effectiveness of its remediation measures, and the completion of its technical investigation.

This article originally appeared on CoinTrust.