Free proxy lists are notoriously unstable. A huge percentage of these proxies are likely dead (non-functional) or extremely slow.
Adversaries use large lists of proxies to hide their identity while attempting to log into accounts (credential stuffing) or launching Distributed Denial of Service (DDoS) attacks [2]. 3. The Risks of Using Free Proxy Lists 15296x Socks4.txt
Such files are often used by security professionals for testing network security or, more commonly, by malicious actors for anonymous web browsing, data scraping, or executing cyberattacks [2]. Free proxy lists are notoriously unstable