A proxy relay is a forwarding path that sends a user’s traffic through another server before it reaches the destination. Instead of connecting directly, the client connects to the relay, and the relay makes the outbound request on its behalf. In some setups this is used for privacy, filtering, or access control; in others it is used to hide the true source of traffic.
In cyber security, proxy relays matter because they can sit in the middle of a session and change who can see what. A trusted relay may only forward encrypted traffic, but a malicious or misconfigured relay can log destinations, metadata, or even unencrypted content. Attackers use proxy relays in fake VPNs, browser extensions, and bot infrastructure to mask activity or enable adversary-in-the-middle behavior. Defenders watch for unexpected proxy settings, unusual extension permissions, and traffic paths that do not match policy.