As if the security news about Yahoo couldn't get any worse, the company disclosed today (Dec. 14) that data pertaining to up to 1 billion user accounts may have been stolen by an unknown party in August 2013. This massive breach, likely the largest on record, is not connected to the previous record-holder, a 2014 data breach that saw 500 million Yahoo accounts compromised by a separate band of intruders. Today's announcement also disclosed that internal secret codes relating to user authorization cookies may have been stolen in 2015 or 2016, permitting an intruder — possibly the same as that in 2014 — to log into Yahoo accounts without a password.