Quantum Computers: Power, Promise, and Security Risk

While artificial intelligence, cloud computing, and data-driven services dominate today’s tech headlines, another seismic shift is quietly approaching — one that could redefine computing as we know it. Quantum computers, once confined to theoretical physics and futuristic think tanks, are now becoming a tangible reality. And with that reality comes both extraordinary potential and serious threats, especially in the realm of cybersecurity.

Tech experts and cybersecurity professionals alike are raising red flags. A recent Tech Trends report by Deloitte, combined with insights from regional specialists, suggests we’re rapidly running out of time to brace ourselves for what’s coming.

Why Encryption Matters More Than Ever

Modern digital infrastructure is built on encryption. Every time you send an email, make a bank transfer, upload data to the cloud, or manage your smart home, encryption silently protects your information from fraud and unauthorized access. It’s the invisible shield that keeps our digital economy running smoothly and securely.

But it’s not just about keeping hackers at bay. Even artificial intelligence models — the backbone of automation, diagnostics, and decision-making systems — depend on reliable, secure, and uncompromised data. A single weak link in this chain can lead to catastrophic consequences, from the collapse of financial systems to critical healthcare failures.

And here’s the catch: the encryption algorithms we rely on today weren’t designed to withstand the brute force capabilities of tomorrow’s quantum machines.

Quantum Computing: A New Kind of Threat

Unlike classical computers that process information in bits — either a 0 or a 1 — quantum computers use qubits, which can exist in multiple states at once, thanks to the principles of superposition and entanglement. This allows them to perform certain types of calculations at speeds unfathomable for even today’s most powerful supercomputers.

What once sounded like science fiction is rapidly materializing. Tech giants like IBM, Microsoft, and Fujitsu, alongside ambitious startups like Atom Computing, are already experimenting with systems exceeding a thousand qubits. Meanwhile, researchers at MIT recently made a breakthrough by linking photons and atoms in a way that dramatically shortens quantum readout times — a longstanding technical obstacle in the field.

The problem? These same quantum computers could, in theory, crack widely used encryption protocols such as RSA and ECC — the very algorithms that underpin secure online banking, encrypted messaging, corporate secrets, and even national security systems.

“This is a critical issue,” warns Zoltán Szöllősi, Partner at Deloitte Hungary’s Cyber Advisory. “If a quantum computer breaks encryption, even decades-old confidential information could suddenly become exposed.”

The Race for Post-Quantum Protection

Fortunately, the global tech community isn’t standing idle. Under the leadership of the U.S. National Institute of Standards and Technology (NIST), an international effort is underway to develop post-quantum cryptographic algorithms. These next-generation protocols are designed to withstand quantum attacks, safeguarding digital signatures, encryption keys, and sensitive data in a post-quantum world.

The challenge, however, is monumental. While algorithm development is progressing, integrating these solutions into existing infrastructures — especially across large enterprises and government systems — is a complex, years-long process.

Deloitte experts advise that companies should start preparing now. Transitioning to new cryptographic standards isn’t as simple as flipping a switch. It involves assessing current algorithms, evaluating potential business and technical risks, and crafting a comprehensive hardware and software upgrade strategy designed for quantum-era resilience.

A New Kind of Cyber Risk: ‘Harvest Now, Decrypt Later’

One particularly alarming threat is already in play. Cybercriminals and hostile state actors are believed to be collecting encrypted data today, with the intention of decrypting it in the future once quantum technology becomes sufficiently advanced. This tactic, ominously dubbed “harvest now, decrypt later”, means that sensitive intellectual property, corporate contracts, medical records, and classified state documents could be silently stockpiled and then exposed years from now.

In response, Deloitte’s cybersecurity specialists recommend immediate action:

• Audit all existing encryption protocols and key management systems
• Evaluate the operational and technical challenges of adopting post-quantum algorithms
• Design a future-proof hardware and software strategy that prioritizes quantum-resistant security standards

Quantum Computing: A Double-Edged Sword

It’s important to remember that quantum computing isn’t solely a threat. Its unprecedented computational power promises breakthroughs in medicine, climate modeling, materials science, and beyond. But as Scibor Lapies, Partner at Deloitte Poland’s Technology and Transformation division, points out, “with these incredible scientific advances come the most significant data security challenges the world has ever faced.”

In an interesting historical note, in 2023, China’s 372-qubit quantum computer didn’t just crack a 48-bit RSA key — it did so in under three minutes. While a 48-bit key is essentially a relic by today’s cybersecurity standards, the demonstration showcased a real-world, practical quantum attack for the first time. The feat underscored how rapidly quantum processing power is improving and why global cybersecurity agencies now treat quantum-readiness as a top-tier strategic priority.