The dramatic cyber attack on the NHS in May brought the health service to its knees as hackers demanded $300 in 'bitcoin' to unlock private patient files.The attack crippled trusts across the UK, with authorities reporting their hospitals' computers being locked up until the ransom was paid.But what is Bitcoin?Here we look at the 21st century currency that exists only in cyberspace.Bitcoin was the first of what have become known as "cryptocurencies".These are forms of digital money that use encryption to secure transactions and control the creation of new units.The popularity of Bitcoin has spawned many copycats - sometimes called "altcoins".To make things more confusing, there are also "second generation" virtual currencies like Ethereum, which has been in the news recently following the hack of the Distributed Autonomous Organisation (DAO) investment platform.Created by a mysterious developer who uses the pseudonym Satoshi Nakamoto, Bitcoins exploded on to the financial scene in 2013, following enormous increases in their value.

In the original Bitcoin white paper, Nakamoto describes his creation as a "peer-to-peer version of electronic cash", allowing "online payments to be sent directly from one party to another without going through a financial institution".bitcoin ptsNakamoto wrote that such a currency uses "cryptographic proof instead of trust, allowing any two willing parties to transact directly with each other without the need for a trusted third party".bán bitcoin onlineThis sort of stateless, bank-free currency uses a distributed, cryptographically secure "blockchain" to record payment transactions.bitcoin apk hackRecording of payments onto the blockchain is powered by users, who offer their computer power.deutsches bitcoin portal

They are rewarded with newly created Bitcoins, and this activity is referred to as mining.converter bitcoin para realBitcoins can be obtained in a number of different ways.bitcoin wallet 64 bitIt's possible to accept them as payment for goods or services.litecoin mining with old computerYou can also buy them directly from individuals or special websites called 'exchanges' that will swap Bitcoins for regular currency.ethereum jobs singaporeBitcoin wallets are simply specially-designed programs that store your Bitcoin, the same way a regular wallet would store your cash.bitcoin goes bustThey can be used either on a desktop computer or a smartphone and can be stored securely on the web so they can be accessed from anywhere.

Mining is a tricky process that involves solving a complex maths problem that takes both time and computing power.The more powerful your computer (and thus, the quicker you can crunch the numbers) means a more difficult problem.Custom-built Bitcoin mining hardware and software is now available, allowing miners to find Bitcoins even faster.Each miner also solves a dual function as they process and secure transactions on the block chain.But the more miners that join, the harder it becomes to find Bitcoins.A Bitcoin miner can be anyone that simply does it for fun right up to someone with the latest equipment who is attempting to mine for profit.Bitcoin miners also join into pools that split the workload and gives each of them a share of the profits.Second-generation cryptocurrencies include altcoins with more advanced functions, that harness the computing power of the blockchain.An example is Ethereum - the blockchain can execute "smart contracts".These are pieces of computer code that can interact with other coded contracts and perform work - for instance moving money around and making decisions.

The DAO platform that was hacked is written into the Ethereum blockchain and can autonomously operate without humans to control the organisation.To decide what investments the DAO makes, its members vote on which proposed contacts will be included in the blockchain.This could be the start of an autonomous financial future dictated by machines rather than humans.'how to get bitcoin', 'bitcoin wallets', 'how to mine' and 'what is a bitcoin miner' Would you ever invest in Bitcoin?TalkTalk, a British phone and broadband provider with more than four million customers, disclosed Friday that intruders had hacked its Web site and may have stolen personal and financial data.Sources close to the investigation say the company has received a ransom demand of approximately £80,000 (~USD $122,000), with the attackers threatening to publish the TalkTalk’s customer data unless they are paid the amount in Bitcoin.In a statement on its Web site, TalkTalk said a criminal investigation was launched by the Metropolitan Police Cyber Crime Unit following “a significant and sustained cyberattack on our website.” “That investigation is ongoing, but  unfortunately there is a chance that some of the following data has been compromised: names, addresses, date of birth, phone numbers, email addresses, TalkTalk account information, credit card details and/or bank details,” the statement continues.

“We are continuing to work with leading cyber crime specialists and the Metropolitan Police to establish exactly what happened and the extent of any information accessed.” A source close to the investigation who spoke on condition of anonymity told KrebsOnSecurity that the hacker group who demanded the £80,000 ransom provided TalkTalk with copies of the tables from its user database as evidence of the breach.The database in question, the source said, appears related to at least 400,000 people who have recently undergone credit checks for new service with the company.However, TalkTalk’s statement says it’s too early to say exactly how many customers were impacted.“Identifying the extent of information accessed is part of the investigation that’s underway,” the company said.It appears that multiple hacker collectives have since claimed responsibility for the hack, including one that the BBC described as a “Russian Islamist group” — although sources say there is absolutely no evidence to support that claim at this time.

Separately, promises to post the stolen data have appeared on AlphaBay, a Deep Web black market that specialized in selling stolen goods and illicit drugs.The posting was made by someone using the nickname “Courvoisier.” This member, whose signature describes him as “Level 6 Fraud and Drugs seller,” appears to be an active participant in the AlphaBay market with many vouches from happy customers who’ve turned to him for illegal drugs and stolen credit cards, among other goods and services.It seems likely that Courvoisier is not bluffing, at least about posting some subset of TalkTalk customer data. dedicated to explaining AlphaBay’s new Levels system, an AlphaBay seller who has reached the status of Level 6 has successfully consummated at least 500 sales worth a total of at least $75,000, and achieved a 90% positive feedback rating or better from previous customers.“Post will be updated shortly,” Courvoisier promised in an AlphaBay message thread Friday.“Data will be supplied in the following format: This roughly tracks the details that TalkTalk has said might have been accessed on customers: Name DOB Address Email Address Telephone Number TalkTalk Account Information Credit Card and Bank Details According to my source, the intrusion started with an attack technique known as SQL injection (SQLi), a method which abuses a misconfiguration in a database that causes the database to cough up or dump information.

The source said the SQLi attack was punctuated by a denial-of-service attack that sought to prevent legitimate users from visiting the targeted site, and that the debilitating assault may have been launched to distract from the database hack.Several individuals on Twitter also have been posting information suggesting they may know how the breach occurred, and that there were only a few thousand customer records exposed in the breach.On October 18, 2015, a person using the screen name “Fearful” and alias “Glubz” reported a vulnerability in the videos section of TalkTalk’s Web site (videos.talktalk.co.uk)., a site that operates as a sort of public clearinghouse for information about unpatched Web site vulnerabilities. said it verified the flaw indeed existed in the TalkTalk videos page, but that no technical details were being disclosed to the public in order to give website owner time to patch the vulnerability without putting its users at risk.Interestingly, a Twitter user with the Twitter handle @Fearful has been posting about expecting a raid from the U.K.

authorities at any minute.The Twitter profile links to the (possibly compromised) Web site elliottg[dot]net, which currently redirects to a page with scrolling images of a blond-haired young man, the TalkTalk logo, and a U.K.A Google-cached version of the site indicates that Glubz has “continuously found website exploits ranging from non critical and critical exploits/bugs.I’ve always wanted to work for a company that specialises in stuff like this and that time has finally come.Being paid for something you enjoy is probably the best job ever. ranks Glubz among its Top 50 Security Researchers, and says Glubz’ Twitter handle is “@Fearful”.TalkTalk apologized for the breach and said that since discovering the breach on Wednesday it has undertaken a full security review of its Web site and had taken “all necessary measures” to secure the site.The company also is offering customers 12 months of free credit monitoring through Noddle, a credit reporting service offered by the credit reference agency CallCredit.

Extortion attacks put victim companies in a bit of bind, because even if they do pay the ransom demand, there is no guarantee the data was not already shared with or stolen by other attackers — or that the extortionists won’t simply go ahead and publish the data even if they are paid.As I noted in a Reddit Ask Me Anything interview Friday, there is, unfortunately, a great deal of room for growth in cyber attacks that leverage some type of ransom or extortion.“It seems like the crooks are getting better situational awareness when they break in somewhere, which of course increases the potential for an opportunistic attack (drive-by download, database hack, malware-laden spam blast) to mushroom into something much bigger and more costly for the victim or organization,” I wrote.ET: Added information about vulnerabilities reported in the video portion of TalkTalk’s Web site. This entry was posted on Saturday, October 24th, 2015 at 10:33 am and is filed under A Little Sunshine, Data Breaches.