SMTP Tunnel – A SOCKS5 proxy disguised as email traffic to bypass DPI

In plain words

SMTP Tunnel is a SOCKS5 proxy that disguises traffic as ordinary SMTP email sessions to evade Deep Packet Inspection firewalls. It runs a local proxy on the client side while the server makes connections appear as legitimate email communication. The tool supports multiple users with individual secrets and IP whitelists, installs via one command on Linux, auto-reconnects on failure, and works with any SOCKS5-compatible application. Built with Python, asyncio, and TLS encryption.

written from the facts on this page · September 2026

From the sources

A high-speed covert tunnel that disguises TCP traffic as SMTP email communication to bypass Deep Packet Inspection (DPI) firewalls. - x011/smtp-tunnel-proxy

In the maker’s words, at launch

A fast SOCKS5 proxy that tunnels your traffic through what looks like normal SMTP email, bypassing Deep Packet Inspection firewalls. How it works: - Client runs a local SOCKS5 proxy (127.0.0.1:1080) - Traffic is sent to server disguised as SMTP (EHLO, STARTTLS, AUTH) - DPI sees legitimate email session, not a…

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