Qubic’s Network Halt Amid Wallet Seed Breach

On 18 October 2026, the Qubic blockchain was temporarily shut down following a security incident that exposed the private keys of more than 1,400 wallets. An attacker exploited predictable wallet‑seed generation, draining approximately 2.94 trillion QU (about $1.4 million) from those accounts. The exploit operated for roughly 104 minutes before validators intervened.

Cause of the Breach

The root cause was the use of JavaScript’s Math.random() function in the wallet‑seed creation process. Math.random() is not designed to provide cryptographically secure entropy, allowing the attacker to reconstruct wallet seeds without resorting to brute‑force attacks. The vulnerability affected wallets created in any browser on iPhone or iPad, in Safari on macOS before 18 October 2026, or in the Qubic iOS app prior to the incident.

Response and Mitigation

  • Chain Freeze: Validators (termed “Computors”) halted the chain at tick 85,371,949, freezing 87.1 % of the compromised funds on‑chain.
  • Exchange Action: MEXC froze the remaining assets within an hour.
  • Software Patch: Qubic released version 4.26.4, correcting the seed‑generation code to use operating‑system cryptographic interfaces for entropy.
  • Network Status: Operations resumed after the patch, with all previously affected funds recovered or secured.

Impact on Market Metrics

  • Close Price (18 Oct 2026): 4.64695 × 10⁻⁷ USD per QU.
  • 52‑Week High (26 Oct 2025): 1.47707 × 10⁻⁶ USD.
  • 52‑Week Low (19 Sep 2026): 3.41092 × 10⁻⁷ USD.
  • Market Capitalization: 66,775,287.254 USD.

The incident underscores the importance of secure random number generation in wallet creation. While the blockchain’s consensus rules remained intact, the vulnerability highlighted a critical software flaw that compromised user funds without altering on‑chain transaction validity.