The utilization of carbon fiber-reinforced polymer (CFRP) materials in electronic equipment encounters notable challenges of electronic warfare operations and the risk of detection by various sensors. A novel ceramic coating comprising TiC/SiOC with added Al2O3 adhesive was formulated to address these issues. The TiC/SiOC-50 wt% Al2O3 coating demonstrated exceptional microwave-effective absorption bandwidth (EAB) of 13.5 GHz, effectively covering the entire Ka-band, while maintaining a thin thickness of 0.60 mm. The TiC/SiOC-80 wt% Al2O3 system exhibited remarkable EM characteristics, including a minimum reflection loss (RLmin) of −58.26 dB, an EAB of 10.74 GHz, and an ultra-thin thickness of 0.38 mm, which sets a new record as the thinnest reported coating in the existing literature. The outstanding electromagnetic performance, coupled with their lightweight and thin characteristics, positions these coatings as highly viable solutions for various electromagnetic shielding and absorption applications in extreme environments.