The Czech Cybersecurity Agency NUKIB would like to draw your attention to the “harvest now, decrypt later” method and its study on the matter from April 23rd 2025:
In addition to its benefits for many industries, quantum computing poses a potential threat to cybersecurity. This is that a sufficiently powerful quantum computer could in the future be able to break most of the cryptographic algorithms in use today. These algorithms protect key aspects of digital security such as communication encryption, authentication and digital signatures. “Harvest now, decrypt later” (HNDL) is a strategy whereby an attacker intercepts and stores encrypted communications today that he cannot yet decrypt. However, he hopes that in the future – with the advent of quantum computers – he will have sufficient means to break the cryptography used and decrypt this data, which may still be valuable in hindsight.
Therefore, measures are actively being taken to prevent quantum attacks. The primary tool is so-called post-quantum cryptography. These are new encryption algorithms that should resist quantum computers. The NUKIB recognises the need for early implementation of post-quantum cryptography and summarises the minimum requirements in the document Minimum Requirements for Cryptographic Algorithms (Czech only). This document reflects not only the ongoing development but also the current knowledge in the field of cryptographic algorithms, including those published by the US National Institute of Standards and Technology (NIST). Their efficient and timely implementation will be key, as will the ability to quickly adopt any updates.
To successfully implement not only new encryption standards, but also any other elements of cybersecurity, up-to-date software and, if possible, hardware should be used. In order to implement post-quantum encryption as quickly as possible, it can be combined with other proven conventional cryptography in a hybrid solution.
More information can be found in the document here: https://nukib.gov.cz/download/publikace/analyzy/HNDL-FINAL.pdf
Translation from Czech to English by deepl, origin of text, more information and further details available https://nukib.gov.cz/cs/infoservis/hrozby/2239-upozornujeme-na-metodu-harvest-now-decrypt-later/
Foto von Glen Carrie auf Unsplash