Collaborate Disseminate
I need to enable hybernation to the LUKS-encrypted drive. My /boot partition is unencrypted hence it stores all kernel images as well as kernel parameters in unencrypted form. For hybernation to work I should specify where the swap file st… Continue reading Is specifying resume_offset for hybernation to LUKS-encrypted drive safe?
We (collectively) salt passwords, then hash them; maybe even run them through something like PBKDF2 first (depending on how the password will be used).
The end result is that we have a string p and map it to a fixed-length string p’ using … Continue reading How certain is it that a shorter password can’t match the salted hash of a long one? [migrated]
A group of Swiss researchers have published an impressive security analysis of Threema.
We provide an extensive cryptographic analysis of Threema, a Swiss-based encrypted messaging application with more than 10 million users and 7000 corporate customers. We present seven different attacks against the protocol in three different threat models. As one example, we present a cross-protocol attack which breaks authentication in Threema and which exploits the lack of proper key separation between different sub-protocols. As another, we demonstrate a compression-based side-channel attack that recovers users’ long-term private keys through observation of the size of Threema encrypted back-ups. We discuss remediations for our attacks and draw three wider lessons for developers of secure protocols…
A group of Chinese researchers have just published a paper claiming that they can—although they have not yet done so—break 2048-bit RSA. This is something to take seriously. It might not be correct, but it’s not obviously wrong.
We have long known from Shor’s algorithm that factoring with a quantum computer is easy. But it takes a big quantum computer, on the orders of millions of qbits, to factor anything resembling the key sizes we use today. What the researchers have done is combine classical lattice reduction factoring techniques with a quantum approximate optimization algorithm. This means that they only need a quantum computer with 372 qbits, which is well within what’s possible today. (The …
Diplomatic code cracked after 500 years:
In painstaking work backed by computers, Pierrot found “distinct families” of about 120 symbols used by Charles V. “Whole words are encrypted with a single symbol” and the emperor replaced vowels coming after consonants with marks, she said, an inspiration probably coming from Arabic.
In another obstacle, he used meaningless symbols to mislead any adversary trying to decipher the message.
The breakthrough came in June when Pierrot managed to make out a phrase in the letter, and the team then cracked the code with the help of Camille Desenclos, a historian. “It was painstaking and long work but there was really a breakthrough that happened in one day, where all of a sudden we had the right hypothesis,” she said…
Brian Krebs writes about how the Zeppelin ransomware encryption scheme was broken:
The researchers said their break came when they understood that while Zeppelin used three different types of encryption keys to encrypt files, they could undo the whole scheme by factoring or computing just one of them: An ephemeral RSA-512 public key that is randomly generated on each machine it infects.
“If we can recover the RSA-512 Public Key from the registry, we can crack it and get the 256-bit AES Key that encrypts the files!” they wrote. “The challenge was that they delete the [public key] once the files are fully encrypted. Memory analysis gave us about a 5-minute window after files were encrypted to retrieve this public key.”…
Continue reading Breaking the Zeppelin Ransomware Encryption Scheme
Extracting private keys directly from the card is nearly impossible. With some acid package destruction and electron microscope work, a skilled team, and enough time, money, and luck you can in theory extract keys but it involves not only… Continue reading How do RSA smartcards prevent key exfiltration?
Quantum computing is a completely new paradigm for computers. A quantum computer uses quantum properties such as superposition, which allows a qubit (a quantum bit) to be neither 0 nor 1, but something much more complicated. In theory, such a computer can solve problems too complex for conventional computers.
Current quantum computers are still toy prototypes, and the engineering advances required to build a functionally useful quantum computer are somewhere between a few years away and impossible. Even so, we already know that that such a computer could potentially factor large numbers and compute discrete logs, and break the RSA and Diffie-Hellman public-key algorithms in all of the useful key sizes…
SIKE is one of the new algorithms that NIST recently added to the post-quantum cryptography competition.
It was just broken, really badly.
We present an efficient key recovery attack on the Supersingular Isogeny Diffie-Hellman protocol (SIDH), based on a “glue-and-split” theorem due to Kani. Our attack exploits the existence of a small non-scalar endomorphism on the starting curve, and it also relies on the auxiliary torsion point information that Alice and Bob share during the protocol. Our Magma implementation breaks the instantiation SIKEp434, which aims at security level 1 of the Post-Quantum Cryptography standardization process currently ran by NIST, in about one hour on a single core…
ENCSecurity markets a file encryption system, and it’s used by SanDisk, Sony, Lexar, and probably others. Despite it using AES as its algorithm, its implementation is flawed in multiple ways—and breakable.
The moral is, as it always is, tha… Continue reading Cryptanalysis of ENCSecurity’s Encryption Implementation