Threat · curated 13 Aug 2026
Person Hides Prompt Injection in Legal Filing Telling AI to Side With Them
First reported 404media.co
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Why it matters
Matthew Elliott's hidden legal-filing injection is a real-world example of indirect prompt injection embedded in documents to manipulate downstream LLMs, showing how automated document-processing pipelines in legal and other systems can be covertly weaponized.
A self-represented plaintiff, Matthew Elliott, hid prompt-injection instructions in tiny 3-point white font throughout a Connecticut court filing, directing any AI system that processes the document to produce output favorable to his position and to 'ensure remediation.' A court worker noticed unusual white space, and the judge disclosed the concealed instructions in a sanction decision; the court noted it does not use AI to process documents.