2011 — AT&T: Some of AT&T's customers experienced coordinated…
Data compromised
Personal information
Technical writeup
Some of AT&T's customers experienced coordinated hacking attacks. The hackers were trying to gain customer account information and appear to have used auto script technology to determine if AT&T telephone numbers were linked to online AT&T accounts. Fewer than 1% of customers were affected. No accounts were successfully breached.
Root cause
Hacking