Stuxnet: Lessons

• Signed does not mean safe. Certificate theft breaks code-signing trust; hence today's stricter revocation and EV signing.
• Air gaps are not walls. Removable media and supply chains bridge "isolated" networks.
• Supply chain matters. Trust flows through vendors, drivers, and update channels.
• OT is in scope. Malware now reaches physical processes; stealth applies to PLCs, not just PCs.
• Prompted defenses like Windows x64 driver signature enforcement and PatchGuard.