Crunchfish makes Digital Cash quantum safe


Crunchfish has applied for a patent that makes Digital Cash resistant to attacks by classical and quantum computers, keeping payment information secure even after large-scale quantum computers has been built. The present invention offers a new paradigm for offline payments that addresses the challenges which can be expected in the era of quantum computing.

The advent of large-scale quantum computing offers great promise to science and society, but brings with it a significant threat to our global information infrastructure. Public-key Infrastructure, widely used on the internet today, relies upon cryptography that is believed to be secure given the computational power available now and in the medium term. However, popular cryptographic schemes based on these hard problems, including RSA and Elliptic Curve Cryptography, will be easily broken by a quantum computer. This will rapidly accelerate the obsolescence of our currently deployed security systems and will have dramatic impacts on any industry, including payments, where information needs to be kept secure.

With quantum computing, all information that is transmitted on public channels is vulnerable to eavesdropping. Encrypted data can also be stored for later decryption once quantum computing becomes available. Bitcoin is one example where previously made transactions are accessible by anyone and puts a substantial amount of Bitcoin at risk. Quantum computing is still a few years into the future. However, the timing when technical innovation leapfrogs are hard to predict and there are already several initiatives taken world-wide on how to address the perceived threat. For instance, The US government has issued a memorandum to define a plan by Q3 2022 to mitigate the risk.

Crunchfish has applied for a Swedish patent protecting Digital Cash by combining two different data integrity schemes. First, payments are negotiated offline by short-range data communication between payer and payee communication devices using a quantum-secure cryptographic key as a shared secret. Successfully negotiated offline payments are stored locally and securely in the devices. Subsequently, payment settlement by broadband data communication is secured by signing the settlement request with another quantum secure cryptographic key.


“Crunchfish demonstrates leadership in offline payments by making Digital Cash secure for quantum computing attacks. It may not be a problem that needs to be addressed today, but a patent application positions the company for the future when the problem becomes acute to solve”, says Joachim Samuelsson, CEO of Crunchfish.



For more information, please contact:

Joachim Samuelsson, CEO of Crunchfish AB

+46 708 46 47 88

This information is information that Crunchfish AB is obliged to publish in accordance with the EU Market Abuse Regulation. The information was provided by the contact person above for publication on 1 April 2022 at 00:01 CET.

Västra Hamnen Corporate Finance AB is the Certified Adviser. Email: Telephone +46 40 200 250.



About Crunchfish –

Crunchfish is a deep tech company developing a Digital Cash platform for Banks, Payment Services and CBDC implementations and Gesture Interaction technology for AR/VR, automotive and digital interfaces. Crunchfish is listed on Nasdaq First North Growth Market since 2016, with headquarters in Malmö, Sweden and with representation in India.

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