The massive data breach announced by credit score giant Equifax Inc (NYSE:EFX) last September keeps getting worse.
The Atlanta-based firm, which has a market cap in excess of US$13bn, initially thought that the details of around 143mln customers had been hacked, although it upped this estimate to 145.5mln in October.
READ: Equifax pummeled after massive cyber attack
But Equifax has now added another 2.4mln to that figure, meaning that as many as 147.9mln people have been affected in some way by the hack. That’s almost half of the US population.
The affected people’s compromised details involves partial driving license data. It did not include social security numbers, which was the focus of earlier probes into the breach and the reason why this group was not identified sooner.
“This is not about newly discovered stolen data,” said Paulino do Rego Barros, Equifax's interim chief executive who took the helm after Richard Smith stepped down in the wake of the hack.
“It's about sifting through the previously identified stolen data, analyzing other information in our databases that was not taken by the attackers, and making connections that enabled us to identify additional individuals.”
Equifax shares, which are down by a quarter since news of the cyber-attack first broke, lost another 0.5% to US$111 in premarket trading on Friday.