CoWoS stands for Chip-on-Wafer-on-Substrate. It is an advanced packaging method that combines compute dies and memory, such as HBM, into one high-density module. By shortening the distance between components, CoWoS enables very high bandwidth and efficient power delivery, which is why it is widely used in AI accelerators and other performance-critical chips.
In cyber security, CoWoS matters because modern attack and defense capabilities depend on hardware supply chains as much as on software. When packaging capacity is concentrated in a few facilities, delays, substitutions, or counterfeit parts can become operational and security risks. Defenders look at CoWoS-class modules during procurement, component validation, firmware trust checks, and hardware attestation. The practical lesson is that secure systems start with trusted assembly, not just trusted code.