This paper proposes a Static RAM Physical Unclonable Function (SRAM PUF) based novel lightweight security subsystem in midrange to high-end IoT SoCs. The proposed subsystem integrates dedicated hardware components optimized for security computations including data encryption, decryption, and authentication. This design shares the computational workload with application processors, improving the overall system efficiency. By utilizing SRAM PUFs, the subsystem provides robust cryptographic key generation and authentication while maintaining a minimal silicon footprint. The architecture ensures secure boot processes and real-time program execution monitoring, addressing the prevalent security challenges in IoT devices. This solution offers a significant advancement in hardware security for IoT, balancing high-security measures with low resource consumption.