Out-of-band (OOB) SQL injection is an attack technique that pentester/red teamers use to exfiltrate data or execute malicious actions when direct or traditional methods are ineffective. Unlike In-band SQL injection, where the attacker relies on the same channel for attack and data retrieval, Out-of-band SQL injection utilises separate channels for sending the payload and receiving the response. Out-of-band techniques leverage features like HTTP requests, DNS queries, SMB protocol, or other network protocols that the database server might have access to, enabling attackers to circumvent firewalls, intrusion detection systems, and other security measures.