SentinelOne researchers have reverse‑engineered Fast16, a 21‑year‑old malware that could silently alter high‑precision calculations in engineering software, potentially undermining critical infrastructure. The discovery shows how sophisticated sabotage can evolve over decades, raising new concerns for the energy sector. State‑sponsored cyber sabotage has ranged from destructive wiper attacks to the infamous Stuxnet, which in 2007 accelerated Iranian centrifuge spin‑up until the machines failed. Fast16, first revealed in a 2017 NSA leak, predates Stuxnet by two years and was designed to spread across networks and manipulate computation processes in specialized software. Fast16 was dated to 2005 and was likely created by a U.S. government agency or ally. The malware targets high‑precision simulation tools such as LS‑DYNA , developed by scientists from Lawrence Livermore National Laboratory , and used for modeling everything from aircraft collisions to crane component strength. Other potential targets include the Portuguese MOHID water‑system model and the Chinese PKPM construction software. The Institute for Science and International Security noted that LS‑DYNA can model nuclear‑weapon physics, suggesting Fast16 could have been aimed at Iran’s nuclear research before Stuxnet. “It focuses on making slight alterations to these calculations so that they lead to failures—very subtle ones, perhaps not immediately apparent,” explained Kamluk, who will present the findings at Black Hat Asia. Guerrero‑Saade added that Fast16 “fits the bill” as an early predecessor to the Olympic Games program, noting that the malware’s stealthy sabotage could have caused equipment to wear out faster or collapse without obvious warning. For the energy industry, the Fast16 revelation underscores the need for robust verification of simulation outputs and tighter controls on software supply chains. As engineering teams increasingly rely on advanced modeling tools, ensuring the integrity of the underlying code will be essential to prevent hidden sabotage that could compromise drilling operations or critical infrastructure.