On Thu, Mar 17, 2022 at 07:51:43PM +0100, egoitz--- via openssl-users wrote: > I think that is the problem, the sha1. That's the specific issue being reported. > So... I have built Openssl 3.0.2 There's no reason for OpenSSL 3.0.2, that might just tighten the restrictions further. OpenSSL 1.0.0 and up all support SHA2-256, you can create and consume SHA-2 certificates with OpenSSL 1.1.1. > I have seen that the own CA uses sha1WithRSAEncryption signature > algorithm. Yes, fix that. > I assume this is one of the things to change, so I have planned to > convert the whole PKI, the whole CA to another supported Signature > algorithm that had no issues with SECLEVEL2. Just set the default digest to sha256, and reissue all the intermediate and leaf certificates. The root CA can stay unchanged, its self-signature is not relevant. > 1 - Is it possible to update a whole CA with 2048 bit public and private > keys (I used in req section of openssl.conf, the default_bits to 2048) > to a Signature algorithm that don't bother the SECLEVEL 2?. SHA2-256 is sufficient. > I mean to have two versions of the same certificate. One for SECLEVEL1 > and one for SECLEVEL2?. I preserve all csr and so.... It is isn't "the same certificate". You can issue new certificates, that all clients can verify, by using SHA2-256. > 2 - I was wondering too another question... although this is not urgent > now. If the CA key pair, is almost expiring what's the proper process of > doing what is supposed to be done?. I assume, it could be : Keys don't expired, certificates do. You can reissue a CA certiifcate with the same key and subject name, but a different expiration time and serial number. > But... I assume I would have to use a different CN for the new CA?. No, you would typically use the same CN if just extending the validity. > Perhaps is this same process the one I need to do.... for converting > certificates from SECLEVEL 1 friendly to SECLEVEL 2 friendly?. Certificate don't have seclevels, they have a signature algorithm, SHA2-256 has long been support by all clients. -- Viktor.