Yahoo is warning users that malicious activity on their accounts may have taken place between 2015 and 2016. It’s the latest development in the internet company’s investigation of a mega-breach that exposed 1 billion users’ data several years ago.
The activity involved the use of forged cookies — strings of data which can be used to allow people to access online accounts without re-entering their passwords.
Yahoo declined to say how many people were affected.
The company said in a statement Wednesday that its investigation “has identified user accounts for which we believe forged cookies were taken or used. Yahoo is in the process of notifying all potentially affected account holders.”
The announcement came hours after the company reportedly reached a new acquisition deal with Verizon, which had offered $4.8 billion for the internet giant last year, before reports of security breaches sent the deal into uncertainty.