RESP (Redis Serialization Protocol)
RESP (REdis Serialization Protocol) is the wire protocol Redis clients and servers use to exchange commands and replies, typically over port 6379. It's a simple, text-based format -- each message type (simple string, error, integer, bulk string, array) starts with a distinct prefix character -- which makes RESP easy for client libraries to parse, and it's defined by Redis's own documentation rather than an IETF RFC the way DNS or SMTP is. RESP itself carries no authentication: Redis's documentation describes it as designed for trusted clients on trusted networks, so anyone who can open a RESP connection can issue any command the server accepts. This is why an internet-reachable Redis port with no password set is an immediately exploitable misconfiguration, not a minor gap -- a 2018 Imperva study found roughly 75% of the open Redis instances it scanned already infected with malware.
By AdminKit team, Netbase JSC · Updated