Security Experts:

Connect with us

Hi, what are you looking for?


Data Protection

Quora Data Breach Hits 100 Million Users

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.

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.

Quora hacked

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.

Related: 92 Million User Credentials Exposed in MyHeritage Data Breach

Related: Facebook Says Hackers Accessed Data of 29 Million Users

Related: Dell Resets User Passwords Following Data Breach

Written By

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.

Click to comment

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Expert Insights

Related Content

Application Security

Cycode, a startup that provides solutions for protecting software source code, emerged from stealth mode on Tuesday with $4.6 million in seed funding.

Data Breaches

GoTo said an unidentified threat actor stole encrypted backups and an encryption key for a portion of that data during a 2022 breach.

Malware & Threats

Microsoft plans to improve the protection of Office users by blocking XLL add-ins from the internet.


A recently disclosed vBulletin vulnerability, which had a zero-day status for roughly two days last week, was exploited in a hacker attack targeting the...


CISA, NSA, and MS-ISAC issued an alert on the malicious use of RMM software to steal money from bank accounts.

Application Security

Many developers and security people admit to having experienced a breach effected through compromised API credentials.


Russia-linked cyberespionage group APT29 has been observed using embassy-themed lures and the GraphicalNeutrino malware in recent attacks.


No one combatting cybercrime knows everything, but everyone in the battle has some intelligence to contribute to the larger knowledge base.