A vulnerability exists where a connection requiring TLS incorrectly reuses an existing unencrypted connection from the same connection pool. If an initial transfer is made in clear-text (via IMAP, SMTP, or POP3), a subsequent request to that same host bypasses the TLS requirement and instead transmit data unencrypted.
pyLoad: SSRF guard bypass via IPv6 6to4/NAT64 transition wrappers of internal IPs
connection reuse ignores TLS requirement