Philipp Muens

12 May 2025

Excited to announce Primefactor! Primefactor is a Research and Development Lab that explores the forefront of cryptographic advancements.

eprint.iacr.orgLattice-based Signature Schemes for BitcoinLattice-based cryptography offers a promising direction for transitioning Bitcoin toward post-quantum security, serving as a secure replacement for currently deployed discrete logarithm signatures. Th...

11 Aug

The Blockstream team just released their 192 page paper on Lattice-based Signature Schemes (for Bitcoin). It also includes an intro to Lattice-based cryptography. eprint.iacr.org/2026/1628

cedarcrypt.orgCedarcrypt 2026 — Applied Cryptography Summer School & ConferenceJoin us for four days of applied cryptography in the Mediterranean. July 13–16, 2026 at AUB Mediterraneo Campus, Paphos, Cyprus.

30 June

Cedarcrypt is right around the corner and the program looks absolutely amazing! cedarcrypt.org Really sad that I can't attend this year 🥲 I hope that there'll be a second installment next year.

eprint.iacr.orgSoK: Private LLM Inference using Approximate Homomorphic EncryptionAlthough recent surveys on privacy-enhancing technologies concluded that FHE cannot feasibly evaluate non-linear activation functions in modern ML architectures, 20 CKKS-based frameworks have since de...

2 June

The Duality Technologies team published a comprehensive SoK on private LLM inference via FHE (with a focus on the CKKS scheme). It’s still inefficient, but FHE has come a long way. I am very hopeful that we'll get there someday. eprint.iacr.org/2026/935

eprint.iacr.orgA gentle introduction to lattice-based cryptographyWe present the quantum-safe Kyber key encapsulation mechanism (ML-KEM) and the Dilithium signature scheme (ML-DSA). We also develop the mathematical background on lattices needed to understand why Kyb...

1 June

Wow! Alfred Menezes just published this 182 page "A Gentle Introduction to Lattice-Based Cryptography" paper. I just skimmed through it, but it looks like an invaluable resource if you want to study lattices and how they're used in (PQ) Cryptography. eprint.iacr.org/2026/1098

eprint.iacr.orgA Decade of Lattice Cryptography\emph{Lattice-based cryptography} is the use of conjectured hard problems on point lattices in~$\R^{n}$ as the foundation for secure cryptographic systems. Attractive features of lattice cryptography...

1 June

Other good resources are (in no particular order): - eprint.iacr.org/2015/939 - eprint.iacr.org/2023/032 - eprint.iacr.org/2024/1287

youtube.com39C3 - How To Minimize Bugs in Cryptography CodeYouTube video by media.ccc.de

15 May

Good talk that shows techniques and tools to implement cryptographic algorithms in a more secure (as in fewer bugs) way. www.youtube.com/watch?v=Lbs8...

wolfssl.comWhy C Remains the Gold Standard for Cryptographic Software - wolfSSLFor production cryptographic software, memory safety alone does not define security. Real-world crypto must run on every platform, maintain stable assumptions

26 Apr

Interesting take on why C should be used for Cryptography implementations. www.wolfssl.com/why-c-remain...

github.comGitHub - Hexens/awesome-fhe-attacks: A curated list of research, articles, tools, and resources focused on attacks against Fully Homomorphic Encryption (FHE)A curated list of research, articles, tools, and resources focused on attacks against Fully Homomorphic Encryption (FHE) - Hexens/awesome-fhe-attacks

25 Apr

This is a nice list with different resources on FHE attacks: github.com/Hexens/aweso... Pairs well with the Security Notions Zoo: securitynotionszoo.com

youtube.comCircularity Based IO, Part 1YouTube video by Simons Institute for the Theory of Computing

19 Apr

Another really good presentation that explains how iO can be constructed from LWE-with-hints in a very intuitive way. Lots of the schemes have been broken, unfortunately. However constructing iO from LWE with minor tweaks is still a promising direction. www.youtube.com/watch?v=NmxZ...

youtube.comLattice-Based Post-Quantum iO from Circular Security with Random Opening AssumptionYouTube video by Simons Institute for the Theory of Computing

18 Apr

This is a great talk that explains why constructing iO from pure LWE is still an open research question. It also dives into the LWE-with-hints line of work and proposes the new Circular Security with Random Opening assumption. www.youtube.com/watch?v=H3Qc... eprint.iacr.org/2025/390

youtube.comIndistinguishable obfuscation. The tech that will solve crypto! - Jordi BaylinaYouTube video by Duct Tape

18 Apr

This is a great review paper that explains the iO construction "Indistinguishability Obfuscation from Functional Encryption" by Bitansky and Vaikuntanathan in a very digestible manner. It's highly recommended to take some notes while reading along. piazza.com/class_profil...

iO is still highly inefficient, unfortunately. I hope that we'll get there at some point as iO unlocks a lot of super interesting use cases: www.youtube.com/watch?v=SNnX... Hardware-based iO seems like a nice stepping stone towards practical iO. eprint.iacr.org/2025/1989.pdf

ubermensch.blogMaking Sense of ZK Virtual MachinesA deep dive into how ZKVMs work — from ZK proofs and circuits through arithmetization to building a working STARK-based ZKVM in Rust.

10 Apr

This is an amazing resource to learn how zkVMs work under the hood: ubermensch.blog/articles/mak...

eprint.iacr.orgA Universal Blinder: One-round Blind Signatures from FHEWe construct compilers that convert any secure signature scheme into a single-round blind signature scheme. An important property of the construction is that the final blind signature has exactly the ...

26 Mar

This is a very interesting paper that uses FHE to turn any signature scheme into a blind signature scheme. Verifiability is ensured using a zkp. It also introduces the concept of "committed verifiable FHE" where the verifier doesn't learn the circuit. eprint.iacr.org/2026/574

eprint.iacr.orgeprint.iacr.org

21 Mar

Really good paper that dives very deep into the intricacies of zkVMs. eprint.iacr.org/2026/525.pdf

eprint.iacr.orgBroken By Design: A Longitudinal Analysis of Cryptographic Failures in Alipay Mobile Payment InfrastructureWe present a systematic security analysis of Alipay's APK signing certificate, issued in 2009 using md5WithRSAEncryption with RSA-1024 and still active in 2026, serving over one billion users. Through...

20 Mar

Interesting paper that shows why it's important to keep your cryptography up to date. eprint.iacr.org/2026/526

eprint.iacr.orgBlind Adaptor Signatures, Revisited: Stronger Security Definitions and Their Construction toward Practical ApplicationsAlthough both blind signatures and adaptor signatures have individually attracted attention, there is little research on combining these primitives so far. To the best of our knowledge, although the ...

16 Jan

I'm a huge fan of Adaptor Signatures and use them in a project I'm currently working on. A new paper was just released that studies Blind Adaptor Signatures which is an interesting combination of Blind Signatures and Adaptor Signatures: eprint.iacr.org/2026/060

antonz.orgGo feature: Secret modeAutomatically erase memory to prevent secret leaks.

10 Jan

Really excited for the new "Secret Mode" that will land in Go v1.26 and will make operations such as key generation more secure. antonz.org/accepted/run...

eprint.iacr.orgEfficient Threshold ML-DSAThreshold signature schemes allow a group of users to jointly generate a digital signature, providing resilience against faults and enhancing decentralization. With the advent of post-quantum cryptogr...

9 Jan

Really great to see more research on Threshold ML-DSA (fka Dilithium): eprint.iacr.org/2026/013 The code for the implementation can be found here: zenodo.org/records/1796...

github.comGitHub - Threshold-ML-DSA/Threshold-ML-DSAContribute to Threshold-ML-DSA/Threshold-ML-DSA development by creating an account on GitHub.

9 Jan

Here's the GitHub repo: github.com/Threshold-ML...

eprint.iacr.orgLifeXP+: Secure, Usable and Reliable Key Recovery for Web3 ApplicationsIn the Web2 world, users control their accounts using credentials such as usernames and passwords, which can be reset or recovered by centralized servers if the user loses them. In the decentralized W...

8 Dec 2025

Key recovery is a tricky problem. This new paper outlines an interesting approach based on natural language stories which utilizes embeddings behind the scenes. It's an interesting solution at the intersection of Cryptography and Machine Learning. eprint.iacr.org/2025/2206

youtube.comDEF CON 33 - Post Quantum Panic: When Will the Cracking Begin, & Can We Detect it? - K KaragiannisYouTube video by DEFCONConference

25 Oct 2025

Very interesting talk when it comes to the SotA of Quantum Computing: www.youtube.com/watch?v=OkVY...

eprint.iacr.orgThreshold ECDSA in Two RoundsWe propose the first two-round multi-party signing protocol for the Elliptic Curve Digital Signature Algorithm (ECDSA) in the threshold-optimal setting, reducing the number of rounds by one compared t...

22 Sept 2025

Great to see some progress towards a Two-Round ECDSA Threshold Signature Scheme: eprint.iacr.org/2025/1696

github.comGitHub - TECDSA/ecdsa_two_roundContribute to TECDSA/ecdsa_two_round development by creating an account on GitHub.

22 Sept 2025

Here's the code for their implementation: github.com/TECDSA/ecdsa...

eprint.iacr.orgContext-Dependent Threshold Decryption and its ApplicationsIn a threshold decryption system a secret key is split across a number of parties so that any threshold of them can decrypt a given ciphertext. We introduce a new concept in threshold decryption call...

11 Sept 2025

This is an interesting paper that allows for a context to be added to Threshold Decryptions: eprint.iacr.org/2025/279

Excited to share my implementation of the paper "Verifiable Timed Signatures Made Practical" by Thyagarajan et al. More specifically I implemented the Verifiable Timed Commitment scheme described in section E.

To maximize learning I constrained myself to only depend on the standard library and zero 3rd party dependencies. The whole code is covered with various tests which you can use to see how the implementation can be used in practice.

github.comGitHub - primefactor-io/vtc: Implementation of the Verifiable Timed Commitment schemeImplementation of the Verifiable Timed Commitment scheme - primefactor-io/vtc

Here's a link to the repository and its documentation: Repository: github.com/primefactor-... Documentation: pkg.go.dev/github.com/p...

Implementing the Verifiable Timed Commitment scheme was definitely a hard nut to crack. I started working on this late last year, but there were a lot of missing pieces I had to put in place (e.g. implement the Linearly Homomorphic Time-Lock Puzzle first).

I also had to do a lot of pen-and-paper math to figure out how everything works. I'm super happy that it's finally out there! I also learned a ton while working on this which is valuable in and of itself.

Using this, timelock capabilities can be brought to Blockchains that don't have a scripting language. It furthermore increases privacy as no data regarding the timelock is stored on-chain (the VTC is shared off-chain).

youtube.comVerifiable timed signatures made practical | Cybersecurity SeminarsYouTube video by Monash Information Technology

One could use this in 2/2 multisigs (e.g. Payment Channels). Before funding the multisig, we could create a signed refund transaction which is timelocked via a VTC. The VTC can be opened after time t which allows one to refund themselves if the co-signer doesn't cooperate.

The VTC implementation described in the paper is really elegant as it uses Linearly Homomorphic Time-Lock Puzzles to implement the proof via a cut-and-choose mechanism. I highly recommend you read the paper or watch this presentation to learn more: www.youtube.com/watch?v=X4vO...

This construction has various applications, but the one I'm focusing on is refund transactions. Rather than using the Blockchain's scripting language you can share an encrypted signature over a refund transaction off-chain. This signature can then be recovered after time t.

A Verifiable Timed Commitment (VTC) allows one to commit to a value that's encrypted "into the future". For example, I can commit to and encrypt a private key in such a way that it can only be decrypted after time t.

eprint.iacr.orgeprint.iacr.org

Verifiability is implemented via a proof which guarantees that the value that can be decrypted after time t is the one that was committed to. In our example we could provide the public key and the proof guarantees that the encrypted private key corresponds to the public key.

Paper: eprint.iacr.org/2020/1563.pdf Repository: github.com/primefactor-... Documentation: pkg.go.dev/github.com/p...

eprint.iacr.orgREFHE: Fully Homomorphic ALUWe present a fully homomorphic encryption scheme which natively supports arithmetic and logical operations over large "machine words", namely plaintexts of the form $\mathbb{Z}_{2^n}$ (e.g. $n=64$). O...

13 Aug 2025

This is a really interesting FHE paper in which BGV is used to build an ALU to do arithmetic as well as logical operations on messages in Z_2^n (e.g. 64 bit machine words). eprint.iacr.org/2025/1449

eprint.iacr.orgVerifiable Timed Signatures Made PracticalA verifiable timed signature (VTS) scheme allows one to time-lock a signature on a known message for a given amount of time $T$ such that after performing a sequential computation for time $T$ anyone ...

12 Aug 2025

Currently deep down the rabbit hole to finish my implementation of "Verifiable Timed Signatures Made Practical" eprint.iacr.org/2020/1563 While doing so I had to update my LHTLP implementation. It now features a range proof and new homomorphic operations: github.com/primefactor-...

plonk.zksecurity.xyzHow to 𝒫𝔩𝔬𝔫𝒦Interactive 𝒫𝔩𝔬𝔫𝒦 Zero-Knowledge Proof Tutorial

6 Aug 2025

ZKSecurity just dropped this truly awesome PlonK tutorial: plonk.zksecurity.xyz

eprint.iacr.orgPost-Quantum Readiness in EdDSA ChainsThe impending threat posed by large-scale quantum computers necessitates a reevaluation of signature schemes deployed in blockchain protocols. In particular, blockchains relying on ECDSA, such as Bitc...

29 July 2025

This is an interesting read on how EdDSA's hash-based key derivation (RFC 8032) can be used to compute PQ-ZKPs for private key ownership proofs: eprint.iacr.org/2025/1368 This is good news as it allows for an easier transition towards Post Quantum secure cryptocurrencies.

ingonyama.comFoundations of High-Speed Cryptography CourseStart with a gentle introduction to core cryptographic primitives, explore the basics of hardware acceleration, and then apply them to build optimized systems with ICICLE.

23 July 2025

Ingonyama just published the first three lessons of their "Foundations of High-Speed Cryptography" course 👀 www.ingonyama.com/foundations-...

eprint.iacr.orgZHE: Efficient Zero-Knowledge Proofs for HE EvaluationsHomomorphic Encryption (HE) allows computations on encrypted data without decryption. It can be used where the users’ information are to be processed by an untrustful server, and has been a popular ch...

18 July 2025

This paper looks really interesting: eprint.iacr.org/2025/770 ZKPs for (F)HE Schemes based on Ring-LWE. FHE + ZKPs are a dream combo.

youtube.comDiamond iO: Lattice-Based Obfuscation without Bootstrapping from Functional Encryption, toward...YouTube video by Simons Institute

9 July 2025

The recording of the Diamond iO talk by the Machina iO team that was held during the Simon Institute's "Obfuscation" workshop was just uploaded: www.youtube.com/watch?v=1RcK...

machina-io.comMachina iO - Blog Post

4 July 2025

This is a great paper that explains how to obtain indistinguishability obfuscation (iO) via recursive Functional Encryption: piazza.com/class_profil... It's basically a simplified version of the [BV15] paper: eprint.iacr.org/2015/163

The Machina iO Team just published a blog post which serves as a great introduction to indistinguishability obfuscation (iO): machina-io.com/posts/unboxi...

Philipp Muens reposted

AccessDenied403

@ad403.bsky.social

1 July 2025

Coinbase MPC wallet library presentation at EthCC m.youtube.com/live/ppeyz_J...

m.youtube.comYehuda Lindell (Coinbase)_Coinbase's cb-mpc Open-Source LibraryYouTube video by [EthCC] Livestream 4

news.dyne.orgThe Longfellow ZK (Google-zk)Analysis of the longfellow-zk implementation, also known as google-zk, for MDOC/mdl selective disclosure of verifable credentials.

30 June 2025

Interesting read about Google’s recent "longfellow-zk" implementation: news.dyne.org/longfellow-z...

youtube.comWorld-leaders in Cryptography: Ralph MerkleYouTube video by Bill Buchanan OBE

27 June 2025

What a great episode with the legend Ralph Merkle. I came for the Cryptography and stayed for the insights into Cryonics and general life lessons. www.youtube.com/watch?v=90py... As I wrote before, the Podcast by @billatnapier.bsky.social is an absolute gem if you're interested in Cryptography.