Qubic has resumed blockchain operations after suspending its network to contain a security vulnerability that allowed attackers to steal approximately $1.4 million worth of QU tokens from 1,404 accounts. The layer-1 blockchain project has introduced a recovery process for affected users, with claims accepted until May 1, 2027.
The network resumed processing at 8:00 p.m. on October 19, moving beyond tick 85,371,949, the point at which operations were halted following the security incident. The suspension was intended to limit further movement of stolen funds while the team addressed the vulnerability and developed a recovery plan.
Qubic’s validators, known as Computors, approved the recovery plan and launched a dedicated reclaim platform through which affected wallet holders can check their eligibility and submit claims. The extended deadline gives impacted users several months to verify their accounts and complete the required recovery procedures.
Wallet Vulnerability Exposed Funds to Theft
The incident involved predictable wallet seeds generated by vulnerable versions of Qubic’s web wallet software. Wallet seeds are critical security components because they help generate the cryptographic keys used to control and authorize transactions involving digital assets.
According to the project, the vulnerability affected seeds created through its web wallet on certain Apple devices and browsers. An insecure random-number generator could produce predictable seeds, potentially allowing attackers to determine wallet credentials and gain unauthorized access to funds.
The weakness raised concerns about the security of wallets created using the affected software, particularly because unpredictable seed generation is essential to protecting cryptocurrency holdings. If an attacker can reproduce a wallet’s seed, the associated funds may be vulnerable even when the legitimate holder has not disclosed any credentials.
Qubic halted its blockchain to limit the potential impact of the incident and prevent further movement of compromised assets while it worked on remediation. The project subsequently restored network operations after its validators approved the recovery arrangements.
Users Urged to Create New Wallets
Qubic said it addressed the vulnerability in web wallet version 4.26.4, released on October 19. However, the software update alone does not eliminate the risk associated with wallets created using earlier versions.
The project has urged users who created wallets with previous web wallet versions to treat those wallets as insecure, upgrade to version 4.26.4 or later, generate new wallets, and transfer their remaining funds as soon as possible.
This precaution is important because updating wallet software may not change the underlying seed or cryptographic credentials of an existing wallet. Creating a new wallet and moving assets to it helps users avoid continued reliance on credentials that may have been exposed by the vulnerability.
Users should also verify that they are accessing the project’s legitimate wallet and recovery services before entering sensitive information or transferring assets. Cryptocurrency transactions are generally difficult to reverse, making careful verification essential during security incidents.
Recovery Process and Security Implications
The reclaim platform provides a formal channel for affected holders to check whether their wallet addresses were impacted and submit claims under the approved recovery plan. Users should follow the project’s official instructions and complete the process before the May 1, 2027 deadline.
While the network was halted, the affected funds were moved into a protected escrow instead of staying exposed.
That made recovery possible.
The quorum approved it, and the network has resumed normal operation.
— Qubic (@_Qubic_) October 20, 2026
The incident highlights the risks associated with weaknesses in wallet generation, even when the underlying blockchain remains operational. Predictable cryptographic seeds can undermine wallet security and expose digital assets to unauthorized access.
For Qubic, restoring network activity is only one part of the response. The recovery process, wallet migration guidance, and remediation of the random-number generator flaw are also central to limiting further losses and rebuilding user confidence.
The project has not indicated in the provided announcement whether all stolen funds can be recovered. Affected users should therefore distinguish between submitting a claim and receiving reimbursement, as the outcome will depend on the terms and implementation of the recovery plan.
The incident underscores the importance of secure random-number generation, timely software updates, and proactive wallet migration when vulnerabilities threaten private-key security across blockchain ecosystems.