OpenSSL 3 migration guide doesn't mention anything about TLSv1 and TLSv1.1

FIPS provider doesn't mention it as well.

But my understanding is that TLSv1 and TLSv1.1 isn't supported by FIPS provider as the latter doesn't implement MD5 which is used by Transport Record Layer of TLS.

Is there any explicit statement about (not) supporting TLSv1 and TLSv1.1?


2 Answers 2


The OpenSSL 3.0 FIPS Provider does not support TLSv1.0 or TLSv1.1. It does support TLSv1.2 and TLSv1.3. It should be noted that the FIPS provider does not implement the TLS protocol itself - but it does supply the various crypto algorithms required to support it.

Of particular importance is the TLS KDF. The TLS KDF for TLSv1.0 and TLSv1.1 is based on MD5 and SHA1. The OpenSSL 3.0 FIPS provider does not implement the MD5 digest. You can see the list of algorithms that it supports on this page:


You will see that under the hashing algorithms section on that page MD5 is not listed.

Under the KDF section it lists the TLS13-KDF and TLS1-KDF. This is slightly confusing but if you follow the link next to the TLS1-KDF it gives more documentation for that. It tells you that the KDF itself support TLSv1.0-TLSv1.2 but that in order to get TLSv1.0/TLSv1.1 support you need the MD5-SHA1 digest which the FIPS provider does not have.

The official security policy for the OpenSSL FIPS module is here:


This again lists all the algorithms the module supports and you can see that only the TLSv1.2 and TLSv1.3 KDFs are listed.


They still support version 1.0 and 1.1 of TLS for legacy reasons, you have more information on https://www.openssl.org/docs/man3.0/man7/migration_guide.html and https://www.openssl.org/docs/man3.0/man3/SSL_CTX_set_security_level.html

  • Please, cite migration guide as I provided it as not mentioning TLSv1. I'm asking about FIPS provider and looking for a statement (quote), not a link to a document. Nov 9, 2022 at 12:57
  • 1
    This results in SSL 3, TLS 1.0, TLS 1.1 and DTLS 1.0 no longer working at the default security level of 1 ......
    – camp0
    Nov 9, 2022 at 12:59
  • It is not what I asked. I'm looking for a reference to a statement like "FIPS does(not) support TLSv1 and TLSv1.2", because FIPS is a different from default provider and supports different set of algorithms irrespective of security level. Nov 9, 2022 at 13:16

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