The agency said the alleged breach was reported by the affected organization and remains under review. It clarified that the use of a particular AI model does not imply the model itself or its provider's infrastructure was compromised, nor that the technology was built for malicious purposes. AEPD did not immediately respond to a request for comment and did not identify the large language model or the targeted organization.
According to AEPD, the case is significant because a third party allegedly used an AI agent to carry out multiple stages of an attack with limited human intervention, underscoring the growing role autonomous systems are playing in cybersecurity incidents. The notification submitted by the affected organization indicated that the agent successfully logged into the system, autonomously searched for application weaknesses, and after identifying a vulnerability, altered personal information and viewed billing records.
The incident emerges as regulators and cybersecurity authorities across the United States and Europe intensify scrutiny of risks posed by increasingly capable AI systems, even as businesses continue adopting the technology at a rapid pace.
Spain has positioned itself as one of Europe's most vocal advocates for a "trustworthy AI" model — one that prioritizes protecting privacy, democracy, minors, and public safety over speed or industry profit.
While AEPD acknowledged that a single case is insufficient to establish a broader trend, it said the notification suggests AI-assisted attacks are moving beyond the theoretical stage and beginning to affect real-world processing of personal data.
The watchdog did not indicate when it would complete its review of the reported breach.
AEPD noted that AI does not create fundamentally new threats but increases the speed, scale, and adaptability of existing malicious techniques, thereby reducing the time available to detect and contain them. The agency added that data controllers, processors, and data protection officers must prepare for a scenario in which the speed of attacks will continue to accelerate.
