Posts tagged CSI
Forbes's "Bitcoin Rival Suffers Devastating Attack" reviews DCI's James Lovejoy's discovery of a '51% Attack'
Forbes's "Bitcoin Rival Suffers Devastating Attack" reviews DCI's James Lovejoy's discovery of a '51% Attack'

“Bitcoin gold, a relatively minor cryptocurrency that split off from the original bitcoin blockchain in late 2017, has suffered a so-called 51% attack resulting in over $72,000 worth of bitcoin gold tokens being double spent.

A 51% attack can occur when malicious cryptocurrency miners take control of tokens' blockchain and is the second time it's now happened to bitcoin gold which saw $18 million worth of bitcoin gold stolen in May 2018.

The price of bitcoin gold, which ranks as the 36th most valuable cryptocurrency according to CoinMarketCap data, jumped following reports of the attack, moving counterintuitively considering the seriousness of an attack of this type and suggesting the market for smaller tokens is still far from maturity…”

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ArticlesAshley JacobsonJames Lovejoy, Security, 51% attacks, CSI
Cryptanalysis of Curl-P and Other Attacks on the IOTA Cryptocurrency

By Ethan Heilman (Boston Uni), Neha Narula (MIT Media Lab), Garrett Tanzer (Harvard), James Lovejoy (MIT Media Lab), Michael Colavita (Harvard), Madars Virza (MIT Media Lab), and Tadge Dryja (MIT Media Lab)

We present attacks on the cryptography formerly used in the IOTA blockchain, including under certain conditions the ability to forge signatures. We developed practical attacks on IOTA’s cryptographic hash function Curl-P-27, allowing us to quickly generate short colliding messages. These collisions work even for messages of the same length. Exploiting these weaknesses in Curl-P-27, we broke the EU-CMA security of the former IOTA Signature Scheme (ISS). Finally, we show that in a chosen-message setting we could forge signatures and multi-signatures of valid spending transactions (called bundles in IOTA).

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Featured, PapersNeha NarulaNeha Narula, Tadge Dryja, Madars Virza, James Lovejoy, IOTA, CSI, Security