98 citations · 416 across the 29 of their papers we have counts for
31 papers · 1 filter
Maximal Extractable Value (MEV) Protection on a DAG
Dahlia Malkhi, Pawel Szalachowski
Many cryptocurrency platforms are vulnerable to Maximal Extractable Value (MEV) attacks, where a malicious consensus leader can inject transactions or change the order of user tran…
Post-Quantum VRF and its Applications in Future-Proof Blockchain System
Zengpeng Li, Teik Guan Tan, Pawel Szalachowski +2
A verifiable random function (VRF in short) is a powerful pseudo-random function that provides a non-interactively public verifiable proof for the correctness of its output. Recent…
Accountable Fine-grained Blockchain Rewriting in the Permissionless Setting
Yangguang Tian, Bowen Liu, Yingjiu Li +2
Blockchain rewriting with fine-grained access control allows a user to create a transaction associated with a set of attributes, while another user (or modifier) who possesses enou…
Exploring HTTPS Security Inconsistencies: A Cross-Regional Perspective
Eman Salem Alashwali, Pawel Szalachowski, Andrew Martin
If two or more identical HTTPS clients, located at different geographic locations (regions), make an HTTPS request to the same domain (e.g. example.com), on the same day, will they…
BBB-Voting: 1-out-of-k Blockchain-Based Boardroom Voting
Sarad Venugopalan, Ivan Homoliak, Zengpeng Li +1
Voting is a means to agree on a collective decision based on available choices (e.g., candidates), where participants agree to abide by their outcome. To improve some features of e…
Decentralized Lightweight Detection of Eclipse Attacks on Bitcoin Clients
Bithin Alangot, Daniel Reijsbergen, Sarad Venugopalan +1
Clients of permissionless blockchain systems, like Bitcoin, rely on an underlying peer-to-peer network to send and receive transactions. It is critical that a client is connected t…
Password-authenticated Decentralized Identities
Pawel Szalachowski
Password-authenticated identities, where users establish username-password pairs with individual servers and use them later on for authentication, is the most widespread user authe…
LaKSA: A Probabilistic Proof-of-Stake Protocol
Daniel Reijsbergen, Pawel Szalachowski, Junming Ke +2
We present Large-scale Known-committee Stake-based Agreement (LaKSA), a chain-based Proof-of-Stake protocol that is dedicated, but not limited, to cryptocurrencies. LaKSA minimizes…
AQUAREUM: Non-Equivocating Censorship-Evident Centralized Ledger with EVM-Based Verifiable Execution using Trusted Computing and Blockchain
Ivan Homoliak, Mario Larangeira, Martin Peresini +1
Distributed ledger systems (i.e., blockchains) have received a lot of attention. They promise to enable mutually untrusted participants to execute transactions while providing the…
A First Look into DeFi Oracles
Bowen Liu, Pawel Szalachowski, Jianying Zhou
Recently emerging Decentralized Finance (DeFi) takes the promise of cryptocurrencies a step further, leveraging their decentralized networks to transform traditional financial prod…
SmartCert: Redesigning Digital Certificates with Smart Contracts
Pawel Szalachowski
The Transport Layer Security (TLS) protocol and its public-key infrastructure (PKI) are widely used in the Internet to achieve secure communication. Validating domain ownership by…
SMACS: Smart Contract Access Control Service
Bowen Liu, Siwei Sun, Pawel Szalachowski
Although blockchain-based smart contracts promise a ``trustless'' way of enforcing agreements even with monetary consequences, they suffer from multiple security issues. Many of th…
Fail-safe Watchtowers and Short-lived Assertions for Payment Channels
Bowen Liu, Pawel Szalachowski, Siwei Sun
The recent development of payment channels and their extensions (e.g., state channels) provides a promising scalability solution for blockchains which allows untrusting parties to…
The Security Reference Architecture for Blockchains: Towards a Standardized Model for Studying Vulnerabilities, Threats, and Defenses
Ivan Homoliak, Sarad Venugopalan, Qingze Hum +3
Blockchains are distributed systems, in which security is a critical factor for their success. However, despite their increasing popularity and adoption, there is a lack of standar…
Towards Forward Secure Internet Traffic
Eman Salem Alashwali, Pawel Szalachowski, Andrew Martin
Forward Secrecy (FS) is a security property in key-exchange algorithms which guarantees that a compromise in the secrecy of a long-term private-key does not compromise the secrecy…
Does "www." Mean Better Transport Layer Security?
Eman Salem Alashwali, Pawel Szalachowski, Andrew Martin
Experience shows that most researchers and developers tend to treat plain-domains (those that are not prefixed with "www" sub-domains, e.g. "example.com") as synonyms for their equ…
StrongChain: Transparent and Collaborative Proof-of-Work Consensus
Pawel Szalachowski, Daniel Reijsbergen, Ivan Homoliak +1
Bitcoin is the most successful cryptocurrency so far. This is mainly due to its novel consensus algorithm, which is based on proof-of-work combined with a cryptographically-protect…
A Security Reference Architecture for Blockchains
Ivan Homoliak, Sarad Venugopalan, Qingze Hum +1
Due to their interesting features, blockchains have become popular in recent years. They are full-stack systems where security is a critical factor for their success. The main focu…
Permissionless Blockchains and Secure Logging
Chunpeng Ge, Siwei Sun, Pawel Szalachowski
The blockchain technology enables mutually untrusting participants to reach consensus on the state of a distributed and decentralized ledger (called a blockchain) in a permissionle…
SmartOTPs: An Air-Gapped 2-Factor Authentication for Smart-Contract Wallets (Extended Version)
Ivan Homoliak, Dominik Breitenbacher, Ondrej Hujnak +3
With the recent rise of cryptocurrencies' popularity, the security and management of crypto-tokens have become critical. We have witnessed many attacks on users and providers, whic…
BlockPKI: An Automated, Resilient, and Transparent Public-Key Infrastructure
Lukasz Dykcik, Laurent Chuat, Pawel Szalachowski +1
This paper describes BlockPKI, a blockchain-based public-key infrastructure that enables an automated, resilient, and transparent issuance of digital certificates. Our goal is to a…
DSTC: DNS-based Strict TLS Configurations
Eman Salem Alashwali, Pawel Szalachowski
Most TLS clients such as modern web browsers enforce coarse-grained TLS security configurations. They support legacy versions of the protocol that have known design weaknesses, and…
Rethinking Blockchain Security: Position Paper
Vincent Chia, Pieter Hartel, Qingze Hum +5
Blockchain technology has become almost as famous for incidents involving security breaches as for its innovative potential. We shed light on the prevalence and nature of these inc…
A Metapolicy Framework for Enhancing Domain Expressiveness on the Internet
Gaurav Varshney, Pawel Szalachowski
Domain Name System (DNS) domains became Internet-level identifiers for entities (like companies, organizations, or individuals) hosting services and sharing resources over the Inte…