ICT Security-Sécurité PC et Internet

It took 24 hours to notice but on the 5th January 2019, Ethereum Classic (ETC), better known as Ethereum’s (ETH) little brother, was hacked using a rare 51% attack.

In essence, a single person was able to control around 60% of the mining power, creating a longer blockchain which gave them the ability to double spend. Something that was picked up by Coinbase and led to the index and others freezing Ethereum Classic from trading. Ethereum Classic is the 18th-largest cryptocurrency, according to CoinMarketCap. 

Understandably people in the industry are worried, so I asked the experts whether more attacks are likely and if so, could a 51% attack hit the larger cryptocurrencies such as Bitcoin?

Not immutable anymore

Nir Kabessa, President of Blockchain at Columbia University, speculates that while difficult, attacks on the larger cryptocurrencies are no longer out of reach.


With both the hash power securing Ethereum Classic and the market cap of its token supply being less than 1/20th that of the Ethereum main chain, it’s not particularly surprising that Classic was successfully 51% attacked.

Learn more / En savoir plus / Mehr erfahren:

https://www.scoop.it/t/securite-pc-et-internet/?&tag=crypto-currency

https://www.scoop.it/t/securite-pc-et-internet/?&tag=cryptojacking

A hacker has made off with roughly $7.4 million in virtual currency after pouncing during an ethereum ICO.

As reported my Motherboard, the hacker took the opportunity to disrupt the Initial Coin Offering (ICO) of CoinDash, a trading platform for cryptocurrencies.

On Monday, CoinDash held its Token Sale event, in which investors were meant to be able to fund apps in development with virtual currency in return for a stake in such applications in an event similar to a crowdfunding campaign.

The CoinDash ICO, like many others in which cryptocurrency "tokens" (CDT) were exchanged for shares in a project, was keenly anticipated by investors.

However, this time, something went terribly wrong.

Learn more / En savoir plus / Mehr erfahren:

http://www.scoop.it/t/securite-pc-et-internet/?&tag=ETHEREUM

http://www.scoop.it/t/securite-pc-et-internet/?&tag=crypto-currency

Ether’s value has rocketed this year, but a hack shows the digital currency faces pitfalls similar to bitcoin’s.

Learn more / En savoir plus / Mehr erfahren:

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=Ethereum

http://www.wired.com/2016/06/50-million-hack-just-showed-dao-human/

http://www.scoop.it/t/luxembourg-europe/?tag=Bitcoin

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=blockchain

http://www.scoop.it/t/securite-pc-et-internet/?tag=Phishing

The value of the digital currency Ethereum has dropped dramatically amid an apparent huge attack targeting an organisation with huge holdings of the currency.

The price per unit dropped to $15 from record highs of $21.50 in hours, with millions of units of the digital currency worth as much as $50 million stolen at post-theft valuations.

At a pre-theft valuation, it works out as a staggering $79.6 million.

Ethereum developers have proposed a fix that they hope will neutralise the attacker and prevent the stolen funds from being spent.

The core Ethereum codebase does not appear to be compromised.

Learn more / En savoir plus / Mehr erfahren:

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=Ethereum

http://www.wired.com/2016/06/50-million-hack-just-showed-dao-human/

http://www.scoop.it/t/luxembourg-europe/?tag=Bitcoin

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=blockchain

Computer programs that run on blockchains are shaking up the financial system. But much of the hype around what are called smart contracts is just that. It’s a brand new field. Technologists are just beginning to figure out how to design them so they can be relied on not to lose people’s money, and—as a new survey of Ethereum smart contracts illustrates—security researchers are only now coming to terms with what a smart contract vulnerability even looks like.

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https://www.scoop.it/t/securite-pc-et-internet/?&tag=ETHEREUM

https://www.scoop.it/t/securite-pc-et-internet/?&tag=Blockchain

https://www.scoop.it/t/21st-century-learning-and-teaching/?tag=blockchain

https://www.scoop.it/t/21st-century-learning-and-teaching/?&tag=Smart+Contracts

The DAO stands for the “Distributed Autonomous Organization,” and while that could very well refer to anything from a blockchain car-share app to a hive of honey bees, this rather boring title stands for something truly remarkable: the first unmanned investment portfolio. It is a proof of concept for what many believe will be the future of finance, with software organizing and overseeing an investment strategy developed through semi-democratic input from the collected investors. It’s secured by the much-ballyhooed Ethereum platform, using a cryptocurrency called Ether as its trading currency, and at first everything seemed to be proceeding according to plan. It was a confirmation of the promise of the blockchain, and proof that the future really is near at hand!

Then, just days after that DAO’s public launch, a lone hacker managed to digitally make off with more than $50 million-worth of Ether, or roughly a third of the overall capital the DAO had raised. More than a setback, this was an existential problem: This was the one, specific thing that was supposed to be impossible under the supervision of the blockchain. Despite all the efforts detailed below, make no mistake: the DAO is dead. What’s important now is containing the damage, and stopping it from ruining trust in Ethereum as a whole.

Learn more / En savoir plus / Mehr erfahren:

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=Ethereum

http://www.wired.com/2016/06/50-million-hack-just-showed-dao-human/

http://www.scoop.it/t/luxembourg-europe/?tag=Bitcoin

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=blockchain

http://www.scoop.it/t/securite-pc-et-internet/?tag=Phishing

Crypto anarchists' dream of decentralized currency faces nightmare scenarios.

Learn more / En savoir plus / Mehr erfahren:

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=Ethereum

http://www.wired.com/2016/06/50-million-hack-just-showed-dao-human/

http://www.scoop.it/t/luxembourg-europe/?tag=Bitcoin

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=blockchain

The code behind the biggest crowdfunded project ever was supposed to eliminate the need to trust humans. But humans are tough to take out of the equation.

Learn more / En savoir plus / Mehr erfahren:

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=Ethereum

http://www.wired.com/2016/06/50-million-hack-just-showed-dao-human/

http://www.scoop.it/t/luxembourg-europe/?tag=Bitcoin

http://www.scoop.it/t/21st-century-learning-and-teaching/?tag=blockchain