OSCP-Like Machines - VulnHub

Beginner/Basic-Level Machines

Bob (Difficulty: Easy, Subject: Basic enumeration, web exploitation)
Brainpan (Difficulty: Easy, Subject: Buffer overflow exploitation)
GoldenEye (Difficulty: Easy, Subject: Web enumeration, SQL injection)
NullByte (Difficulty: Easy, Subject: Web enumeration, basic Linux privilege escalation)
Pluck (Difficulty: Easy, Subject: Web exploitation, file inclusion)
Sedna (Difficulty: Easy, Subject: Directory traversal, file inclusion)

Intermediate Machines

Retired (Difficulty: Medium, Subject: Linux enumeration, privilege escalation)
Colt (Difficulty: Medium, Subject: Web exploitation, credential stuffing)
Tibra (Difficulty: Medium, Subject: OSINT, Linux privilege escalation)

Machines Covering Active Directory or Other Relevant Skills

MicroVuln (Difficulty: Medium, Subject: Active Directory enumeration, SMB exploitation)
Razorback (Difficulty: Medium, Subject: Active Directory enumeration, Kerberos exploitation)

Machines Testing Enumeration Skills

Rocky (Difficulty: Medium, Subject: Network enumeration, service identification)
Vulnix (Difficulty: Medium, Subject: Linux enumeration, Sudo exploitation)

Web Exploitation Focus

Surveillance (Difficulty: Medium, Subject: Web enumeration, XSS and RCE exploitation)
Maverick (Difficulty: Medium, Subject: Web application vulnerabilities, PHP exploitation)

Resources For Walkthrough: