UPDATE: The Wall Street Journal reports that Amazon researchers discovered the Fable 5 vulnerability that effectively transformed the model into an unguardrailed version known as Mythos 5. According to the report, after consultations with the White House, Anthropic CEO Dario Amodei declined to implement a patch. In response, President Trump issued a national security export-control order restricting foreign access to the model. Because Anthropic could not reliably enforce nationality-based restrictions through its API, the company ultimately disabled the affected models for all users.