Where this was said
The Software Trail: LSDyna and Nuclear Physics
At 20:15 · chapter starts 18:33
With the knowledge that FAST16 targeted high-precision math, Jags and Vitaly search old systems for software containing the same strings of bytes embedded in FAST16's rules engine. The results point to complex physics modeling software — the kind used to simulate bridge stress tests or car crash dynamics. [1] — Juan Andrés Guerrero Saade "The string of bytes in FAST16's code matched LSDyna, a physics modeling program. A think tank report revealed that Iranian nuclear scientis…" 18:50 But one software package stands out: LSDyna, short for Livermore Software Dynamic Analysis. When Jags searches for LSDyna online, he stumbles upon a report from the Institute for Science and International Security — 'the good ISIS' — which documents that Iranian nuclear scientists were publicly using LSDyna for calculations involving explosive materials for nuclear payloads. This is the key link: FAST16 was designed to corrupt calculations in the exact software Iranian nuclear scientists were using to design nuclear bombs. Vitaly's initial horror makes sense: this malware could theoretically corrupt any safety-critical engineering calculation — bridges, cars, aircraft — raising profound ethical questions about the limits of cyber sabotage.
The string of bytes in FAST16's code matched LSDyna, a physics modeling program. A think tank report revealed that Iranian nuclear scientists were using LSDyna specifically to simulate explosive materials for nuclear payloads — confirming FAST16's likely target with chilling precision.
FAST16 was designed to corrupt calculations in LSDyna (Livermore Software Dynamic Analysis), a complex physics modeling program used by Iranian nuclear scientists for explosive materials simulations.
FAST16 would stay dormant until it detected very specific pressure calculations consistent with simulating a nuclear explosion, only then corrupting the math.
FAST16 hid silently on computers until it detected the specific pressure calculations used to simulate a nuclear explosion. Then it corrupted the math just enough to produce consistently wrong answers — on every machine, every time. Scientists would blame themselves long before suspecting their computers.
