The popular question-and-answer website Quora informed users on Monday that their information may have been stolen after someone gained unauthorized access to its systems.
Quora said it discovered the breach on November 30 and the incident is still being investigated. Do date it has determined that the attacker, described as a “malicious third party,” could have obtained information on roughly 100 million users, including name, email address, hashed password, data imported from linked networks, public content and actions (e.g. questions, answers, comments, and upvotes), and non-public content and actions (e.g. answer requests, downvotes, and direct messages).
According to Quora CEO Adam D'Angelo, users who posted anonymously are not impacted and a vast majority of the compromised data was already public on Quora. Payment card information and social security numbers are not at risk as this type of data is not collected by Quora.
The company is in the process of notifying affected users and resetting their passwords. It pointed out that “not all Quora users are affected, and some were impacted more than others.”
“While the passwords were encrypted (hashed with a salt that varies for each user), it is generally a best practice not to reuse the same password across multiple services, and we recommend that people change their passwords if they are doing so,” D’Angelo said.
Law enforcement has also been alerted – Quora hopes authorities can help identify the attacker – and a forensics and security firm has been called in to assist in the investigation.
Quora has not shared any information on the attack itself, but believes it has identified the root cause and claims to have taken steps to address the issue.
The company has set up an FAQ page where users can find information on resetting their password, obtaining a copy of their data, deleting their account, and some of the steps taken by Quora in response to the breach.
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