The vulnerability affected applications on Apple and Android smartphones and was discovered in late August. Facebook fixed the problem earlier this month. It’s unclear if the bug was ever used in an attack.
Facebook recently announced a breach of its primary platform that affected nearly 50M accounts.
This week, a previously undisclosed breach led to Google closing the consumer version of its Google Plus social network.
Facebook shares are down 0.5% to $157.13.
Previously: Facebook -2.6% after disclosing security problem (Sept. 28)
Previously: WSJ: Google didn't disclose spring Google Plus breach (Oct. 8)
Now read: Facebook: Use This Opportunity »
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