DUBLIN, Dec 17 (Reuters) - The lead European Union data

privacy regulator for Meta fined the social media giant

251 million euros ($263.5 million) on Tuesday for a 2018

Facebook security breach that affected 29 million users.

Meta notified Ireland's Data Protection Commission at the

time that cyber attackers had exploited a vulnerability in

Facebook's code that impacted the "View As" feature that lets

users see what their own profile looks like to someone else.

That led to a breach in personal data including users' full

name, contact details, location, place of work, date of birth,

religion, gender and their children's personal data, the DPC

said.

"By allowing unauthorised exposure of profile information,

the vulnerabilities behind this breach caused a grave risk of

misuse of these types of data," DPC Deputy Commissioner Graham

Doyle said in a statement.

Meta remedied the breach shortly after its discovery, the

DPC said. Of the 29 million Facebook accounts impacted globally,

about 3 million were based in the EU and European Economic Area.

The DPC is the lead EU regulator for most of the top U.S.

internet firms due to the location of their EU operations in

Ireland.

It has so far fined Meta almost 3 billion euros for breaches

under the bloc's General Data Protection Regulation (GDPR)

introduced in 2018, including a record 1.2 billion euro fine in

2023 that Meta is appealing.

Meta said it will also appeal Tuesday's decision and that it

has a wide range of measures in place to protect users across

its platforms.

"We took immediate action to fix the problem as soon as it

was identified, and we proactively informed people impacted as

well as the Irish Data Protection Commission," a spokesperson

for Meta said in a statement.

($1 = 0.9527 euros)