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September 26, 2016updated 30 Sep 2016 2:56pm

Yahoo! breach – the pressure is building following the world’s biggest data breach

Yahoo! faces calls to reveal more details about the data hack of 500 million accounts.

By Alexander Sword

Questions are being asked on why Yahoo! took two years to discover the breach and inform the public.

The delay in the breach discovery means that the information stolen has been ‘in the wild’ for over 24 months with users totally unaware that their personal information had been compromised.

Scale is staggering - Denham

Scale is staggering – Denham

Elizabeth Denham, the UK Information Commissioner in Britain, said: “The vast number of people affected by this cyber attack is staggering. The US authorities will be looking to track down the hackers but it is our job to ask serious questions of Yahoo on behalf of British citizens and I am doing that today.”

The impact is already far reaching. BT and Sky customers are being urged to change their email account passwords as they may have been affected by the breach following email service outsourcing deals between the supplier and Yahoo!

Could this happen again? Breach Notification – Under the General Data Protection Regulation which is expected to become EU law companies will be forced to disclose certain types of breaches immediately to the authorities. This breach notification  requirement would force companies to admit they had been hacked.

Yahoo! is being asked to give many more details in additional to its statement which it issued on September 22nd.

The Yahoo! Data statement in full:

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A recent investigation by Yahoo! Inc. (NASDAQ:YHOO) has confirmed that a copy of certain user account information was stolen from the company’s network in late 2014 by what it believes is a state-sponsored actor. The account information may have included names, email addresses, telephone numbers, dates of birth, hashed passwords (the vast majority with bcrypt) and, in some cases, encrypted or unencrypted security questions and answers. The ongoing investigation suggests that stolen information did not include unprotected passwords, payment card data, or bank account information; payment card data and bank account information are not stored in the system that the investigation has found to be affected. Based on the ongoing investigation, Yahoo believes that information associated with at least 500 million user accounts was stolen and the investigation has found no evidence that the state-sponsored actor is currently in Yahoo’s network. Yahoo is working closely with law enforcement on this matter.

Yahoo is notifying potentially affected users and has taken steps to secure their accounts. These steps include invalidating unencrypted security questions and answers so that they cannot be used to access an account and asking potentially affected users to change their passwords. Yahoo is also recommending that users who haven’t changed their passwords since 2014 do so.

Yahoo encourages users to review their online accounts for suspicious activity and to change their password and security questions and answers for any other accounts on which they use the same or similar information used for their Yahoo account. The company further recommends that users avoid clicking on links or downloading attachments from suspicious emails and that they be cautious of unsolicited communications that ask for personal information. Additionally, Yahoo asks users to consider using Yahoo Account Key, a simple authentication tool that eliminates the need to use a password altogether.

Online intrusions and thefts by state-sponsored actors have become increasingly common across the technology industry. Yahoo and other companies have launched programs to detect and notify users when a company strongly suspects that a state-sponsored actor has targeted an account. Since the inception of Yahoo’s program in December 2015, independent of the recent investigation, approximately 10,000 users have received such a notice.

Additional information will be available on the Yahoo Security Issue FAQs page,, beginning at 11:30 am Pacific Daylight Time (PDT) on September 22, 2016.


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