'No matter what password you use, I will break it in a fraction of a second', one of Israel's cyber pioneers on what quantum computing actually does to encryption

[SchrodingersCat]

Prof. Maj.-Gen. (res.) Isaac Ben-Israel, one of the founding architects of Israel's modern cybersecurity apparatus and former head of the Israel Space Agency, told the Jerusalem Post Podcast that quantum computing will eventually wipe out today's encryption entirely, describing what a mature quantum computer would do to the passwords protecting banks, governments and militaries in blunt terms, no matter what password you use, in a fraction of a second I will break it. The scale of the speed gap he described isn't merely 100 or 1,000 times faster than a classical computer, he put it closer to 10 to the 20th or 30th power, a number he noted we all know how to write down and none of us can really picture

Ben-Israel drew a sharp distinction between two separate areas of quantum research advancing right now, quantum computing and quantum communication. Quantum computing doesn't make hackers better at breaking into a system, it destroys the encryption protecting whatever they find once they're already inside, turning brute force password cracking from an impossibly slow process into something trivial. The fix, he said, comes in two forms, first new post-quantum mathematics that even a quantum machine can't crack in reasonable time, though the algorithms that exist today remain slow and unready for wide adoption, with roughly a 10-year lag expected before industry fully migrates to them

The second and stranger fix, in his view where the world eventually lands, is quantum entanglement itself, since something done on one quantum computer can register on another arbitrarily far away with nothing physically traveling in between, no wire, no signal, nothing to intercept and no password to steal. China has already put a satellite in orbit using exactly this kind of entanglement based communication, and Tel Aviv University students launched a satellite two years ago as an early step toward the same capability. Ben-Israel estimated roughly ten years to solve the main remaining obstacle, interference between quantum elements that gets worse as more are added, but was careful to temper expectations about availability, these will be enormous, ultracold machines drawing enormous amounts of electricity, there will be no more than a few in the world, and a quantum computer in every home is more than 50 years away, if ever

'No matter what password you use, I will break it in a fraction of a second' | The Jerusalem Postwww.jpost.com

[HollywoodHogan92]

The 10 to the 20th or 30th power scale comparison is such a good way to communicate the actual gap, it's not an upgrade, it's a completely different category of speed that normal intuition just can't grasp

[Delulu67]

The distinction between quantum computing breaking encryption versus quantum communication making interception physically impossible is the clearest explanation of these two different fields I've come across

[Leopard85]

No password to steal because nothing travels between the two entangled points at all is one of the stranger implications of physics I've ever tried to wrap my head around

[SilverSurfer51]

The 10 year lag for industry actually adopting post-quantum algorithms once they exist is the detail that should worry people more than the raw quantum computer timeline itself, that's a long exposure window

[NovaPrime]

China already having an operational entanglement based communication satellite while most people have never even heard quantum communication discussed as separate from quantum computing shows how far ahead the practical deployment already is

[Danny47]

A quantum computer in every home being 50 plus years away if ever is a good, honest tempering of expectations, this is never going to be consumer hardware the way computing power historically has been

[Luca]

The ultracold, enormous power draw requirement explaining why big tech is investing in nuclear power specifically to feed these machines ties this directly into a lot of the current AI energy demand conversation too

[SpinState]

This is a clarifying interview for understanding why Q-Day discussions keep splitting into two different, sometimes confused, conversations about breaking existing encryption versus building unbreakable new communication

[SignalFlow Depot]

The interference problem getting worse the more quantum elements you add is exactly the same scaling challenge every quantum computing story eventually comes back to regardless of which country or company is working on it

[DarkMatter]

Worth remembering someone this senior in an actual national cyber apparatus saying this so plainly carries real weight, this isn't hype from a startup trying to sell quantum hardware

[GateSeed70]

The phrase "fraction of a second" is where my eyebrows went up. Quantum algorithms can provide extraordinary speedups for certain problems, but that does not mean a quantum computer turns every computational problem into an instant calculation.

Grover's algorithm is the usual example people bring up for searching an unstructured space. It provides a quadratic speedup, which is significant, but quadratic is not the same as instantaneous. A sufficiently large symmetric key still represents a huge search space. That is why moving to stronger key sizes can provide substantial protection against this particular class of quantum speedup.

Shor's algorithm is the bigger headache for RSA and elliptic-curve cryptography because it changes the complexity of the underlying mathematical problems much more dramatically. That is why post-quantum cryptography is focused heavily on replacing those public-key mechanisms.

So the expert quoted in the article may well be making a useful warning, but readers should resist translating it into "quantum computers make brute force free." They do not. Different cryptographic primitives face different levels of risk.

[MiniElliot]

The most useful thing about a provocative headline like this is that it gets people talking about a subject that normally lives deep inside engineering documents. Quantum computing can sound abstract until someone connects it to something familiar, such as logging into a bank account or sending a private message.

But after getting people's attention, the technical explanation needs to follow. A quantum computer is not simply a faster classical computer, and there is no universal quantum algorithm that instantly solves every password problem. The threat is concentrated in particular mathematical structures and depends heavily on the scale and reliability of the quantum hardware.

That nuance should not be mistaken for reassurance that nothing needs doing. Public-key cryptography is foundational infrastructure, and changing foundational infrastructure takes time. Standards have to be selected, libraries updated, hardware tested and old systems retired.

So I can live with the dramatic headline if the article leaves readers with the right conclusion: don't panic about your password tomorrow morning, but do take the underlying cryptographic transition seriously. The boring preparation is what prevents the dramatic scenario later.

[CipherMonk83]

The comparison I would make is with the move away from older cryptographic standards. Nobody waits until an obsolete cipher is being actively broken at scale before beginning every migration. The difficulty is that quantum computing gives us a much less precise deadline.

That uncertainty makes it tempting to do nothing. If the useful quantum computer is thirty years away, why spend money today? But if replacing the relevant infrastructure takes ten years and sensitive information has a twenty-year lifetime, waiting ten years is already uncomfortable.

There is also a supply-chain issue. A company might be ready to upgrade its servers but depend on a vendor whose hardware or firmware cannot support the new algorithms. Large organisations have layers upon layers of dependencies like this, which is why a cryptographic inventory is such a valuable first step.

So perhaps the sensible interpretation of the article is not "panic because your password is doomed." It is "start asking where your cryptography lives, how long it needs to remain secure, and how difficult it would be to replace." Those are questions worth answering before the headlines become much less theoretical.

[Niamh_52]

A useful way of looking at the claim is to imagine two separate locks. One lock is the password you type. The other is the cryptographic machinery your device uses to communicate securely with a server. Quantum computing is much more directly threatening the second lock than the first.

That distinction gets lost because "encryption" sounds like one universal thing. In reality, modern security systems combine several techniques. Public-key cryptography may establish trust or exchange keys, while symmetric encryption protects the actual session data. Passwords may be processed through specialised password-hashing functions rather than encrypted at all.

For example, when you log into a website, the site does not normally need to keep a readable copy of your password. It can store a password hash and compare your login attempt against it. A quantum computer does not simply ask the hash to reveal the password. There are attacks against search problems, but they do not amount to a magic universal password decoder.

So I would push back on the literal wording while agreeing with the broader warning. The quantum transition is serious, especially for RSA and elliptic-curve systems, but saying "every password is broken in a fraction of a second" gives people the wrong mental model.

[LowKey32]

There is a slightly amusing contradiction in some of these discussions: people hear "quantum computing threatens encryption" and immediately start worrying about whether their Netflix password is safe. Meanwhile, a huge percentage of real-world account compromises still happen because someone reused a password from a website that was breached in 2018.

Quantum computing does not eliminate phishing. It does not stop someone guessing a password like Password123. It does not patch an unprotected server or prevent an employee from clicking a malicious attachment. Those problems remain firmly in the classical-computing era.

Where quantum computing really changes the conversation is around cryptographic assumptions that have been considered secure for decades. RSA and elliptic-curve systems are deeply embedded in certificates, secure connections, signatures and identity infrastructure. Replacing them requires considerably more than telling users to choose longer passwords.

So I would separate the two discussions. Keep doing basic cybersecurity properly today, while engineers work on the much longer transition to quantum-resistant cryptography. One does not replace the other.

[Neil57]

The headline made me think about the difference between encryption and authentication, because people often use those words almost interchangeably. Encryption is about keeping information secret; authentication is about establishing who is communicating with whom and whether something has been tampered with

Quantum attacks on public-key cryptography can affect both. If an attacker can solve the mathematical problem behind a public-key scheme, they may potentially decrypt information protected by that scheme or forge signatures that systems use for authentication. That is a much broader issue than simply guessing someone's password

For example, a browser needs to know that the server it is talking to is actually the bank rather than a criminal sitting between the connection. Certificates and digital signatures help establish that trust. If those mechanisms become vulnerable, secure communication can become much harder to guarantee

That is why I think the most useful question after reading this story is not "Should I change my password?" It is "Are the services I depend on moving toward post-quantum cryptography?" The first is sensible security hygiene; the second is the long-term infrastructure question

[Taker04]

The cybersecurity pioneer angle is interesting because people in national security tend to think about infrastructure rather than individual passwords. A statement like this is probably intended to make the issue memorable, and on that level the dramatic wording has done its job

Still, there is a difference between communicating urgency and communicating technical detail. Saying "your password can be broken in a fraction of a second" could lead somebody to conclude that changing from one password to another is pointless. That would be exactly the wrong lesson

Good password hygiene still matters enormously. Unique passwords, password managers, MFA and phishing resistance protect against attacks that do not require anything remotely resembling a quantum computer. If an attacker can steal your session cookie or convince you to approve a login, they have no reason to spend billions building a quantum machine

The better takeaway is that quantum computing creates a future cryptographic migration problem on top of the ordinary security problems we already have. Unfortunately, the latter remain much more likely to ruin your Tuesday

[Darren]

One thing I would challenge is the idea that there will be a single moment when quantum computing "breaks encryption." Even if a sufficiently capable machine exists, different systems will have different algorithms, key sizes, implementations and migration states

Some organisations may have already moved to quantum-resistant mechanisms. Others may still have ancient equipment running vulnerable software. Some data may have forward secrecy protections that limit what a later compromise can reveal. Other systems may have been designed in ways that make historical traffic much easier to attack

So the transition will probably be uneven and messy. There will be periods where conventional and post-quantum systems coexist, and attackers will naturally target whichever vulnerable corner is easiest to exploit

That is actually a good argument for crypto-agility. If a system can swap algorithms without redesigning everything from scratch, responding to future cryptographic breakthroughs becomes much easier. The best quantum defence may turn out to be good software architecture as much as exotic mathematics.

[Sophie86]

The headline is certainly punchy, but the phrase "no matter what password you use" needs a bit of unpacking. Quantum computing does not mean a machine can simply guess any password instantly. The big theoretical threat is to particular cryptographic problems, especially the public-key systems used for things like key exchange and digital signatures

If the article is talking about Shor's algorithm, that is a much more precise claim. A sufficiently capable, fault-tolerant quantum computer could attack the mathematical assumptions behind RSA and elliptic-curve cryptography far more efficiently than a conventional computer. That could have enormous consequences, but it is not the same as instantly brute-forcing every password on the planet

Passwords are also often protected by hashing rather than being stored as reversible encryption. An attacker trying to crack a password hash still has to search the password space, and quantum algorithms do not turn a random 20-character password into a trivial problem. Good password managers and strong authentication therefore remain useful

Still, the warning deserves attention. If a senior cybersecurity figure is trying to get people to think about the issue now, that is probably because replacing cryptographic infrastructure takes years. The headline may be dramatic, but the underlying message about preparing early is quite reasonable

[SlayedRebellion]

A point that gets overlooked is that organisations have wildly different exposure. A supermarket loyalty account and a classified research archive do not need the same cryptographic migration timetable

If a piece of information is worthless after a week, harvesting it today for decryption ten years from now is not especially useful. If the information is a trade secret that remains valuable for thirty years, the situation is completely different. The lifetime of the secret matters as much as the predicted arrival of the quantum capability

That suggests a sensible migration strategy: start with systems holding information that has long-term confidentiality requirements, then work outward. At the same time, replace vulnerable public-key mechanisms as they come up for normal maintenance rather than waiting for an emergency

It is less exciting than putting a giant countdown clock on Q-Day, but risk management usually works better when it is based on actual assets and consequences. Quantum computing is a new threat model, not an excuse to stop doing ordinary threat modelling

[Harbour]

One practical concern that deserves more attention is harvest-now-decrypt-later. An attacker does not necessarily need a quantum computer today to benefit from a future quantum computer

Imagine someone intercepts encrypted communications containing a company's five-year research programme. The ciphertext may be useless to them today, but if they can store it cheaply and a capable quantum computer appears later, the information could suddenly become readable. The same applies to government communications, long-lived personal records and intellectual property

That changes the timeline because the relevant question becomes "How long does this information need to remain secret?" If the answer is twenty years, waiting twenty years to begin replacing vulnerable cryptography is obviously not a great plan

It is a little like putting documents in a safe whose lock you know will eventually become obsolete. You do not need someone standing outside with the future lock-picking machine today to justify buying a new safe. The possibility that the contents will still matter later is enough

[RightAbout]

What I find reassuring is that the cryptographic community has not been sitting around waiting for quantum computers to arrive before thinking about this. Post-quantum algorithms are already being standardised and evaluated, precisely because the migration cannot happen overnight

There is a healthy amount of caution involved too. A new algorithm is not automatically trustworthy just because it is designed to resist known quantum attacks. Cryptographers have to study its mathematics, implementations have to be tested, and protocols have to be engineered around it. There can also be side-channel vulnerabilities even when the underlying algorithm is sound

That is why hybrid approaches are interesting. For a transition period, systems can combine conventional and post-quantum mechanisms so that an attacker has to compromise both sets of assumptions. It is not a magic solution, but it can provide a useful bridge while organisations migrate

So the situation feels less like an approaching cliff and more like a very large infrastructure upgrade. Expensive, complicated and easy to underestimate, but something that can be planned for if people start early enough

[Sophie89]

There is a danger in reading this as though a giant quantum computer is sitting in a basement somewhere waiting to attack everyone's Gmail account. The engineering challenge is still enormous. Fault-tolerant quantum computing at the scale needed for serious cryptanalysis is not the same thing as having a machine with a few thousand noisy physical qubits

Error correction is a huge part of the problem. A useful logical qubit can require many physical qubits, and the computation needed to attack real cryptographic keys has to run reliably for a very large number of operations. That is a long way from the small demonstrations we see in research announcements

But uncertainty about the timetable cuts both ways. If a company has equipment that will be replaced in two years, perhaps the quantum issue is easy to handle during the normal upgrade cycle. If a satellite, industrial controller or medical device is expected to run for twenty years, waiting for a precise prediction of the first cryptographically useful quantum computer is much less sensible

So yes, the headline is sensational. No, that does not make the planning unnecessary. Security people have to make decisions before the threat becomes convenient to measure