Claude users hit by login session theft and account hijacking
Anthropic's Claude users suffered information-stealing attacks and login session hijacking. Infostealers stole login sessions, leading to usage the account holders had not made being consumed. On September 10, users continued to complain of account hijacking.
Key facts
- Affected organization
- Anthropic
- Incident type
- Hacking & intrusion
- Occurred / detected
- Not confirmed
- Scale of damage
- Claude user accounts hijacked and usage consumed without authorization
- Cause / method
- Login session theft by infostealers
- Location
- South Korea
Timeline
- Account hijacking and usage depletion among Claude users from infostealers stealing login sessions came to light.
- Complaints from Claude users about account hacking and hijacking continued.
3 related reports
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Anthropic breach exposes data from 112 Claude business accounts in South Korea
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Unauthorized access to Anthropic's internal systems through a vulnerability in third-party business software exposed information from 112 Claude business accounts in South Korea. The exposed data included names, email addresses, account and organization identifiers, and usage and spending metrics, while the company said conversations and payment information were not accessed. The Personal Information Protection Commission (PIPC) launched a formal investigation on November 10, and it was subsequently confirmed that Anthropic reported the intrusion to South Korean authorities 21 days after detecting it and notified customer companies after 28 days.
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The summary and key facts are written by AI from related reports and may contain errors. Check the original articles and the organization’s official statements for accurate details.