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Cybersecurity
The Quantum Threat Is Already Here: Why Cybersecurity Must Reinvent Itself Before It Is Too Late
3 minutes of reading
Published on 20 April 2026
The Greatest Change In Digital Security Will Not Come From An Attack… But From Physics
For decades, cybersecurity has been built on an apparently solid foundation: mathematical difficulty.
Modern encryption—the one that protects our communications, transactions and data—relies on the fact that certain problems are practically impossible to solve within a reasonable time frame.
But that assumption is about to break.
Not because of an incremental advance.
Not because of a new type of malware.
But because of a radical change in the way we compute: The arrival of quantum computing.
1. The day cryptography stops working
There is a concept that is becoming increasingly present across the industry: Q-Day.
It is the moment when quantum computers will be able to break today’s cryptographic algorithms efficiently.
When that happens:
- Digital certificates will no longer be reliable.
- Electronic signatures will be forgeable.
- Encrypted communications will be decipherable.
- Digital identities will lose their foundation of trust.
And most critically: There will be no immediate fix.
Because migrating global cryptographic infrastructure is not a patch.
It is a structural transformation that can take years.
2. The silent attack that is already happening
One of the biggest mistakes is to think the problem will begin once a sufficiently powerful quantum computer exists.
In reality, it has already begun.
Attackers are adopting a strategy known as: “Harvest now, decrypt later.”
The model is simple:
- Intercept encrypted data today.
- Store it.
- Decrypt it in the future.
This means that: Data that appears secure today may already be compromised… even if we don’t yet know it.
Especially long-life data:
- Financial information.
- Intellectual property.
- Government data.
- Medical records.
- Industrial secrets.
The quantum threat is not future. It is a present risk with deferred impact.
3. The hidden problem: we don’t know what we are protecting
Before protecting, we must understand.
And here lies one of the greatest challenges: Most organisations lack real visibility into their cryptography.
They do not know:
- Which algorithms their systems use.
- Where they are deployed.
- Which certificates are active.
- What dependencies exist across applications or libraries.
This creates a critical situation: You cannot defend what you cannot see.
This lack of visibility translates into what is already known as: Cryptographic debt.
4. The post-quantum transition: a massive-scale challenge
The solution is not about changing a single algorithm.
It involves:
- Replacing cryptographic standards
- Upgrading legacy systems
- Reconfiguring entire infrastructures
- Coordinating multiple technological layers
And doing so without:
- Disrupting operations
- Creating incompatibilities
- Introducing new risks
We are talking about a transformation that impacts:
- Networks
- Applications
- Devices
- Identities
- Historical data
5. New standards, new rules
In response to this scenario, new post-quantum cryptography standards are already being defined.
These algorithms:
- Are designed to withstand quantum attacks
- Replace current public-key systems
- Introduce new security models
However, their adoption is not immediate.
6. Time as a new risk factor
Cybersecurity has always been about real-time protection.
But the quantum paradigm introduces a new dimension: time.
We now need to think about:
- Data that must remain secure for decades
- Systems that will continue operating in the future
- Information that could be decrypted years from now
Cybersecurity shifts from being reactive to becoming prospective.
7. Automation and intelligence: keys to the transition
The complexity of this change makes manual management unfeasible.
The transition to a “quantum-safe” environment requires:
- Automated cryptographic inventories
- Continuous risk assessment
- Impact-based prioritization
- Large-scale change orchestration
8. Governance: the decisive factor
Beyond technology, the real challenge is governance.
Because this change involves:
- Long-term decisions
- Sustained investments
- Cross-functional coordination
9. A strategic opportunity, not just a risk
Organizations that act early will:
- Reduce future exposure
- Improve resilience
- Gain a competitive advantage
Conclusions
Quantum computing is not just a technological advance.
It is a breaking point.
The question is: Are we protecting today the information that will still be critical in 10 or 20 years?
Cybersecurity is no longer only about defending systems.
It is about preserving trust over time.
