2688968 - HTTP Status 500 - Signature validation of SAML2Assertion failed - SAP Cloud Platform NEO Environment

Application can not be reached in SAP Cloud Platform using a Corporate Identity Provider.

• The following error can be seen in the screen:
   
  HTTP Status 500 - An internal application error occurred
    
• Application log shows the following:
   
  #ERROR#Authentication failed. Reason: Signature validation of SAML2Assertion failed. com.sap.security.saml2.lib.common.SAML2Exception: Signature not valid!
   
• SAML trace (as per e.g. KBA: 2461862 - Collecting SAML traces with Chrome or FireFox) shows the following:
    
  [...]
  "request_method": "POST",
  [...]
  "response_status": 500,
  [...]
  "saml": <...>
  [...]

SAP Cloud Platform, Neo environment

SAML, IDP, corporate IDP, HTTP Status 500, An internal application error occured, Authentication failed, Signature validation, SAML2Assertion failed, NEO, SCP NEO, SAP Cloud Platform , KBA , BC-NEO-SEC-IAM , Authentication, Authorization(Cloud Platform Neo) , Problem