Qubic has suspended its layer-1 blockchain after an attacker exploited a wallet security flaw and stole about 2.94 trillion QU tokens, valued by the project at roughly $1.4 million, from more than 1,400 accounts. The network stop prevented further movement of most of the funds, but it also leaves users waiting for a formal recovery decision.
In an Oct. 18 statement, Qubic said the incident was linked to wallet recovery seeds generated with insufficient randomness. The project said 87.1% of the stolen tokens remained on the network when operations were halted, while the remaining 12.9% had already been sent to crypto exchange MEXC.
Attack traced to vulnerable seed generation
According to Qubic, the exploit did not result from a compromise of the blockchain protocol itself. Instead, the attacker targeted wallets created under software that produced weak recovery seeds, making the private keys derived from them easier to reconstruct.
The project said several wallet categories were affected. These included seeds generated through any browser on iPhone or iPad devices before Oct. 18, 2026, seeds created through Safari on Mac before the same date, and seeds generated through the Qubic iOS application before July 2025.
In its security update, Qubic said developers fixed the issue in web wallet version 4.26.4. The reported change replaced JavaScript’s Math.random() with crypto.getRandomValues(), a function intended for cryptographically secure randomness.
Network halted to contain stolen funds
Qubic said it suspended the blockchain at tick 85,371,949 to stop additional transfers. Based on the project’s figures, around 2.56 trillion QU, or 87.1% of the stolen total, was still inside the network when processing stopped.
The remaining 379.26 billion QU, or 12.9%, had reached MEXC. Qubic said the exchange restricted the receiving account within about an hour after being contacted.
MEXC later suspended QUBIC deposits and withdrawals at the project’s request. XT also announced a suspension on Oct. 18, citing wallet upgrades and maintenance for both the QUBIC and KASPLEX networks.
Patched software does not settle older wallet risk
While Qubic says the flaw in seed generation has been corrected for new wallets, the project has not said that recovery phrases created under the vulnerable software are now safe. That means previously affected wallets may remain exposed even though the original bug has been addressed.
The team said it is identifying compromised wallets and plans to publish a full technical investigation after a recovery plan is settled. For now, the exact scope of wallets at continuing risk has not been resolved beyond the categories already listed by the project.
Recovery plan still awaits approval
Qubic has not announced when normal blockchain operations will resume. Any step to recover or redistribute the frozen funds is waiting on a decision by the network’s operators, known as Computors, who take part in Qubic’s consensus process.
The project has not confirmed that any stolen tokens have been returned to affected users. It also has not said whether a final plan would reverse unauthorized transfers, release frozen tokens through another mechanism, or compensate victims separately.
The next confirmed step is a vote on recovery proposals once the core team finishes its review of compromised wallets. Until that happens, the halted network and exchange restrictions remain central to containing the impact of the exploit.
Source: crypto.news