Brazilian courts have already recorded at least 44 decisions citing the term "prompt injection," a technique that involves hiding commands directed to artificial intelligence systems within documents to attempt to manipulate the automated analysis of a case. In half of these decisions, 22 cases, the court confirmed having found the hidden command inserted in a procedural filing by one of the parties.
The exclusive survey was conducted by Jusbrasil at CBN's request, which analyzed decisions from 19 courts and the Superior Court of Justice published between November 2025 and July this year. The figures reflect only cases that were detected and recorded in the decisions themselves, with possible underreporting, as well as proceedings whose data is not available, such as those under seal.
The most common concealment technique is white font on white background, invisible to the human reader but readable by AI. This modality accounts for 15 of the identified cases in the analyzed decisions. The practice seeks to induce the artificial intelligence system to alter its analysis or provide favorable responses to the party that inserted the hidden command.
