Comprehensive and Detailed Explanation:

Containers share the same host operating system kernel, unlike VMs which run isolated kernels. This shared kernel increases the attack surface — a compromise in one container can potentially affect the entire host if kernel-level access is obtained.

From CEH v13 Courseware:

Module 14: Hacking Web Applications → Container Security

“Containers are less secure because they share the host kernel. Attackers compromising the container can exploit vulnerabilities in the shared OS.”