HACKERS may have accessed the data of 500 million Yahoo users during an attack on the internet platform.
Yahoo has urged Australian users to change their passwords and other security details to protect themselves in light of the 2014 breach.
Yahoo claimed only 200 million users were affected when the breach happened, but this week it upped that figure to 500 million.
The company said US authorities were investigating the massive breach that could have resulted in the theft of names, email address, birth dates, passwords and security questions and answers.
There are concerns this data could have been used to hack into Yahoo users' other digital accounts, the ABC reported.
"Based on the ongoing investigation, Yahoo believes that information associated with at least 500 million user accounts was stolen," the company said in a media statement.
"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." - ARM NEWSDESK
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