3574634 - OAuth2 based authentications via Security Material in Cloud Integration fails with error 'unable to find valid certification path'

In Cloud Integration, via security material, the following OAuth2 based authentications can be configured: 

• OAuth2 Client Credentials
• OAuth2 SAML Bearer Assertion
• OAuth2 Authorization Code 

Using any of them in outbound TLS based adapter configuration in a Cloud Integration flow and below error happens: 

sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

Important to note, that the HTTP based target endpoint configured in the adapter can be accessed via TLS , meaning the target server trusts the CPI client. Validate this by using Connectivity Test functionality of Cloud Integration under TLS tab with Valid Server Certificate Required checkbox enabled. If this works fine to the target endpoint it means the SSL connection is working between CPI and target server. 

Cloud Integration

SAP Integration Suite

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