SSRF protocol smuggling involves an attacker injecting one TCP protocol into a dissimilar TCP protocol. A classic example is using gopher (i.e. the first protocol) to smuggle SMTP (i.e. the second protocol):
The keypoint above is the use of the CRLF character (i.e. %0D%0A) which breaks up the commands of the second protocol. This attack is only possible with the ability to inject CRLF characters into a protocol.
Almost all LDAP client libraries support plaintext authentication or a non-ssl simple bind. For example, the following is an LDAP authentication example using Python 2.7 and the python-ldap library:
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