HISPI Project Cerebellum HISPI PROJECT CEREBELLUM

Hidden Prompt Injection in Brazilian Labor-Court Petition Reportedly Tried to Manipulate Galileu

May 13, 2026

According to recent reports, Galileu—an AI tool employed by Brazil's labor courts—detected hidden manipulative instructions in an initial petition before the 3rd Labor Court of Parauapebas. The embedded text was said to instruct the AI to superficially contest the petition while avoiding a thorough review of supporting documents. Remarkably, Galileu is reported to have alerted the judge and effectively blocked the hidden content from processing. As a result, the judge had the opportunity to manually scrutinize the material before imposing any procedural consequences.

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Matched TAIM controls

Suggested mapping from embedding similarity (not a formal assessment). Browse all TAIM controls

Alleged deployer
conselho-superior-da-justica-do-trabalho, tribunal-regional-do-trabalho-da-8a-regiao, 3a-vara-do-trabalho-de-parauapebas, judicial-system-of-brazil, brazilian-labor-courts
Alleged developer
tribunal-regional-do-trabalho-da-4a-regiao, conselho-superior-da-justica-do-trabalho
Alleged harmed parties
epistemic-integrity, judicial-integrity, judicial-system-of-brazil, brazilian-labor-courts, defendants-in-brazilian-labor-cases

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Source

Data from the AI Incident Database (AIID). Cite this incident: https://incidentdatabase.ai/cite/1497

Data source

Incident data is from the AI Incident Database (AIID).

When citing the database as a whole, please use:

McGregor, S. (2021) Preventing Repeated Real World AI Failures by Cataloging Incidents: The AI Incident Database. In Proceedings of the Thirty-Third Annual Conference on Innovative Applications of Artificial Intelligence (IAAI-21). Virtual Conference.

Pre-print on arXiv · Database snapshots & citation guide

We use weekly snapshots of the AIID for stable reference. For the official suggested citation of a specific incident, use the “Cite this incident” link on each incident page.