Claude AI Accounts Hit by Widespread Unauthorized Charges as Malicious Extensions Steal Tokens
Accounts for Anthropic's Claude AI have recently been targeted by widespread unauthorized charges, primarily because malicious Chrome extensions stole session tokens. The tokens allowed attackers to bypass the login process and charge credit cards linked to the accounts. The incidents affected users in Taiwan, Canada and the United States, highlighting risks involving browser extensions and payment security.
As of July 20, 2026, reports had not disclosed the exact date of the incidents or the number of victims. Some victims had lost more than NT$10,000, while certain accounts were charged repeatedly. Because Anthropic's payment interface does not allow users to remove credit cards directly and responses from human customer support have been slow, users have had to disable suspicious extensions and contact their banks to dispute the charges and limit their losses.
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The history behind this eventClaudeBleed Flaw in Claude Chrome Extension Could Let Malicious Extensions Hijack AI Agent
Anthropic’s Claude Chrome extension can operate webpages on a user’s behalf, giving it access to tab content and sensitive data. Cybersecurity firm LayerX named the design flaw ClaudeBleed, warning that malicious extensions requiring no special permissions could cross trust boundaries and hijack the AI agent. The flaw highlights the security risks created as browser-based AI tools gain broader privileges.
As of July 20, 2026, Anthropic had released a patched version, but LayerX testing found that version 1.0.70 still did not eliminate the underlying design issue. Attackers could potentially continue using malicious Chrome extensions to control Claude and exfiltrate data. No information has been disclosed about the number of victims, financial losses or the patch’s release date, and users should continue limiting extension permissions and checking installation sources.
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