Hacker used Anthropic's Claude to attack French far-right organizations
A French-speaking hacker reportedly used Anthropic's Claude AI system to conduct a spring 2026 cyberattack campaign against at least 42 European political organizations, media outlets, and think tanks, gaining internal access to at least 14 targets and exfiltrating 12–26 gigabytes of data including donor information and emails.
What happened
A French-speaking hacker conducted a spring 2026 cyberattack campaign using Anthropic's Claude AI system to automate attacks against European political organizations, media outlets, think tanks, and technical service providers. The hacker targeted at least 42 entities and gained internal access to at least 14 of them.
The attacker exfiltrated between 12 and 26 gigabytes of data from compromised targets. The stolen data included donor and member information from a political party, payment provider data, a mailbox containing 15,000 messages, and other files.
Reported impact
The campaign compromised multiple European organizations, with several French targets identified. At least one French far-right political party was among the breached organizations.
Governance controls
Anthropic published a security report on September 11, 2026, disclosing the incident and describing how the hacker used Claude to conduct the attack campaign.
Classification
Sources and evidence
Sources not yet published
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