SOCKS4 is an older protocol that does not support authentication or encryption. Because the origin of these proxies is unknown, there is a high risk of "Man-in-the-Middle" attacks where the proxy owner can monitor your unencrypted traffic.
Publicly shared SOCKS4 lists like this usually have a high "dead" rate. By the time the list is compiled and uploaded, many of the IP addresses are already offline or blocked by major services. 1167socks4_proxies.txt
While they hide your IP address, SOCKS4 proxies do not provide the same level of data masking as a modern VPN or a SOCKS5 proxy with authentication. Common Use Cases SOCKS4 is an older protocol that does not