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The headline is pretty scary: “China’s Quantum Computer Scientists Crack Military-Grade Encryption.”
No, it’s not true.
This debunking saved me the trouble of writing one. It all seems to have come from this news article, which wasn’t bad but was taken wildly out of proportion.
Cryptography is safe, and will be for a long time
EDITED TO ADD (11/3): Really good explainer from Dan Goodin.
In 2018, Australia passed the Assistance and Access Act, which—among other things—gave the government the power to force companies to break their own encryption.
The Assistance and Access Act includes key components that outline investigatory powers between government and industry. These components include:
- Technical Assistance Requests (TARs): TARs are voluntary requests for assistance accessing encrypted data from law enforcement to teleco and technology companies. Companies are not legally obligated to comply with a TAR but law enforcement sends requests to solicit cooperation.
- Technical Assistance Notices (TANs): TANS are compulsory notices (such as computer access warrants) that require companies to assist within their means with decrypting data or providing technical information that a law enforcement agency cannot access independently. Examples include certain source code, encryption, cryptography, and electronic hardware.
- Technical Capability Notices (TCNs): TCNs are orders that require a company to build new capabilities that assist law enforcement agencies in accessing encrypted data. The Attorney-General must approve a TCN by confirming it is reasonable, proportionate, practical, and technically feasible.
It’s that final one that’s the real problem. The Australian government can force tech companies to build backdoors into their systems.
This is law, but near as anyone can tell the government has never used that third provision.
Now, the director of the Australian Security Intelligence Organisation (ASIO)—that’s basically their FBI or MI5—is threatening to do just that:
ASIO head, Mike Burgess, says he may soon use powers to compel tech companies to cooperate with warrants and unlock encrypted chats to aid in national security investigations.
[…]
But Mr Burgess says lawful access is all about targeted action against individuals under investigation.
“I understand there are people who really need it in some countries, but in this country, we’re subject to the rule of law, and if you’re doing nothing wrong, you’ve got privacy because no one’s looking at it,” Mr Burgess said.
“If there are suspicions, or we’ve got proof that we can justify you’re doing something wrong and you must be investigated, then actually we want lawful access to that data.”
Mr Burgess says tech companies could design apps in a way that allows law enforcement and security agencies access when they request it without comprising the integrity of encryption.
“I don’t accept that actually lawful access is a back door or systemic weakness, because that, in my mind, will be a bad design. I believe you can these are clever people design things that are secure, that give secure, lawful access,” he said.
We in the encryption space call that last one “nerd harder.” It, and the rest of his remarks, are the same tired talking points we’ve heard again and again.
It’s going to be an awfully big mess if Australia actually tries to make Apple, or Facebook’s WhatsApp, for that matter, break its own encryption for its “targeted actions” that put every other user at risk.
Really interesting analysis of the American M-209 encryption device and its security.
Matthew Green wrote a really good blog post on what Telegram’s encryption is and is not.
EDITED TO ADD (8/28): Another good explainer from Kaspersky.
From the Federal Register:
After three rounds of evaluation and analysis, NIST selected four algorithms it will standardize as a result of the PQC Standardization Process. The public-key encapsulation mechanism selected was CRYSTALS-KYBER, along with three digital signature schemes: CRYSTALS-Dilithium, FALCON, and SPHINCS+.
These algorithms are part of three NIST standards that have been finalized:
NIST press release. My recent writings on post-quantum cryptographic standards.
EDITED TO ADD: Good article:
One – ML-KEM [PDF] (based on CRYSTALS-Kyber) – is intended for general encryption, which protects data as it moves across public networks. The other two –- ML-DSA [PDF] (originally known as CRYSTALS-Dilithium) and SLH-DSA [PDF] (initially submitted as Sphincs+)—secure digital signatures, which are used to authenticate online identity.
A fourth algorithm – FN-DSA [PDF] (originally called FALCON) – is slated for finalization later this year and is also designed for digital signatures.
NIST continued to evaluate two other sets of algorithms that could potentially serve as backup standards in the future.
One of the sets includes three algorithms designed for general encryption – but the technology is based on a different type of math problem than the ML-KEM general-purpose algorithm in today’s finalized standards.
NIST plans to select one or two of these algorithms by the end of 2024.
IEEE Spectrum article.
Slashdot thread.
This isn’t good:
On Thursday, researchers from security firm Binarly revealed that Secure Boot is completely compromised on more than 200 device models sold by Acer, Dell, Gigabyte, Intel, and Supermicro. The cause: a cryptographic key underpinning Secure Boot on those models that was compromised in 2022. In a public GitHub repository committed in December of that year, someone working for multiple US-based device manufacturers published what’s known as a platform key, the cryptographic key that forms the root-of-trust anchor between the hardware device and the firmware that runs on it. The repository was located at https://github.com/raywu-aaeon/Ryzen2000_4000.git, and it’s not clear when it was taken down.
The repository included the private portion of the platform key in encrypted form. The encrypted file, however, was protected by a four-character password, a decision that made it trivial for Binarly, and anyone else with even a passing curiosity, to crack the passcode and retrieve the corresponding plain text. The disclosure of the key went largely unnoticed until January 2023, when Binarly researchers found it while investigating a supply-chain incident. Now that the leak has come to light, security experts say it effectively torpedoes the security assurances offered by Secure Boot.
[…]
These keys were created by AMI, one of the three main providers of software developer kits that device makers use to customize their UEFI firmware so it will run on their specific hardware configurations. As the strings suggest, the keys were never intended to be used in production systems. Instead, AMI provided them to customers or prospective customers for testing. For reasons that aren’t clear, the test keys made their way into devices from a nearly inexhaustive roster of makers. In addition to the five makers mentioned earlier, they include Aopen, Foremelife, Fujitsu, HP, Lenovo, and Supermicro.
This is really neat demo of the security problems arising from reusing nonces with a symmetric cipher in GCM mode.
Meta has threatened to pull WhatsApp out of India if the courts try to force it to break its end-to-end encryption.
It’s yet another hardware side-channel attack:
The threat resides in the chips’ data memory-dependent prefetcher, a hardware optimization that predicts the memory addresses of data that running code is likely to access in the near future. By loading the contents into the CPU cache before it’s actually needed, the DMP, as the feature is abbreviated, reduces latency between the main memory and the CPU, a common bottleneck in modern computing. DMPs are a relatively new phenomenon found only in M-series chips and Intel’s 13th-generation Raptor Lake microarchitecture, although older forms of prefetchers have been common for years.
[…]
The breakthrough of the new research is that it exposes a previously overlooked behavior of DMPs in Apple silicon: Sometimes they confuse memory content, such as key material, with the pointer value that is used to load other data. As a result, the DMP often reads the data and attempts to treat it as an address to perform memory access. This “dereferencing” of “pointers”—meaning the reading of data and leaking it through a side channel—is a flagrant violation of the constant-time paradigm.
[…]
The attack, which the researchers have named GoFetch, uses an application that doesn’t require root access, only the same user privileges needed by most third-party applications installed on a macOS system. M-series chips are divided into what are known as clusters. The M1, for example, has two clusters: one containing four efficiency cores and the other four performance cores. As long as the GoFetch app and the targeted cryptography app are running on the same performance cluster—even when on separate cores within that cluster—GoFetch can mine enough secrets to leak a secret key.
The attack works against both classical encryption algorithms and a newer generation of encryption that has been hardened to withstand anticipated attacks from quantum computers. The GoFetch app requires less than an hour to extract a 2048-bit RSA key and a little over two hours to extract a 2048-bit Diffie-Hellman key. The attack takes 54 minutes to extract the material required to assemble a Kyber-512 key and about 10 hours for a Dilithium-2 key, not counting offline time needed to process the raw data.
The GoFetch app connects to the targeted app and feeds it inputs that it signs or decrypts. As its doing this, it extracts the app secret key that it uses to perform these cryptographic operations. This mechanism means the targeted app need not perform any cryptographic operations on its own during the collection period.
Note that exploiting the vulnerability requires running a malicious app on the target computer. So it could be worse. On the other hand, like many of these hardware side-channel attacks, it’s not possible to patch.
Slashdot thread.
Apple announced PQ3, its post-quantum encryption standard based on the Kyber secure key-encapsulation protocol, one of the post-quantum algorithms selected by NIST in 2022.
There’s a lot of detail in the Apple blog post, and more in Douglas Stabila’s security analysis.
I am of two minds about this. On the one hand, it’s probably premature to switch to any particular post-quantum algorithms. The mathematics of cryptanalysis for these lattice and other systems is still rapidly evolving, and we’re likely to break more of them—and learn a lot in the process—over the coming few years. But if you’re going to make the switch, this is an excellent choice. And Apple’s ability to do this so efficiently speaks well about its algorithmic agility, which is probably more important than its particular cryptographic design. And it is probably about the right time to worry about, and defend against, attackers who are storing encrypted messages in hopes of breaking them later on future quantum computers.
Sidebar photo of Bruce Schneier by Joe MacInnis.