Operating System vulnerabilities can include:

• Privilege Escalation
• Buffer Overflow
• Remote Code Execution
• Information Disclosure

Windows

Common Windows vulnerabilities:

• Null Session
• RPC/DCOM
• SMB
• LM Password Hash
• IIS vulnerabilities

Mac OS

Common Mac vulnerabilities:

• Dock Vulnerability
• Remote Control
• Security-Keychain Vulnerability
• Mail Vulnerability

Linux

Common Linux vulnerabilities:

• Ret2libc
• Insecure sudo
• SUID

Android

Common Android vulnerabilities

• Vulnerable apps from the App Store

iOS

Common iOS vulnerabilities

• Vulnerable apps from Apple's App Store