  Blacklists are a widely-used Internet security mechanism to protect Internet
users from financial scams, malicious web pages and other cyber attacks based
on blacklisted URLs. In this demo, we introduce PhishChain, a transparent and
decentralized system to blacklisting phishing URLs. At present, public/private
domain blacklists, such as PhishTank, CryptoScamDB, and APWG, are maintained by
a centralized authority, but operate in a crowd sourcing fashion to create a
manually verified blacklist periodically. In addition to being a single point
of failure, the blacklisting process utilized by such systems is not
transparent. We utilize the blockchain technology to support transparency and
decentralization, where no single authority is controlling the blacklist and
all operations are recorded in an immutable distributed ledger. Further, we
design a page rank based truth discovery algorithm to assign a phishing score
to each URL based on crowd sourced assessment of URLs. As an incentive for
voluntary participation, we assign skill points to each user based on their
participation in URL verification.
