Your Claude quota has vanished out of nowhere? Anthropic confirms the account was hacked
Multiple Claude users found their quotas mysteriously drained without using the service. Anthropic confirmed that hackers used malware to steal login sessions, illegally access accounts, and secretly consume API call quotas. The incident was first discovered by British independent AI advisor Grant Duvall on August 4th. On that day, he was not working, yet his Claude Max 20x account usage continued to rise sharply.