3602426 - Exception during authentication: ERROR [CODE-4230] Invalid assertion: Unable to verify XML signature(StatusCode: , StatusMessage: )

Indexserver shows following errors:

[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514579 d Authentication   SAMLAuthenticator.cpp(00276) : libxmlsec ERROR
...
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514585 d Authentication   SAMLAuthenticator.cpp(00279) : func: xmlSecHDBKeyStoreFindKey
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514587 d Authentication   SAMLAuthenticator.cpp(00280) : errorObject: 
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514588 d Authentication   SAMLAuthenticator.cpp(00281) : errorSubject: xmlSecHDBKeyStoreFindKey
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514589 d Authentication   SAMLAuthenticator.cpp(00282) : reason: 1
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514591 d Authentication   SAMLAuthenticator.cpp(00283) : msg: found no cert for entity id: XX

...

[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514749 i Authentication   SAMLAuthenticator.cpp(00405) : Unable to verify XML signature
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514752 i Authentication   MethodSAML.cpp(00103) : unsuccessful login attempt with SAML ticket!
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514756 d Authentication   ManagerAcceptor.cpp(00339) : evaluate failed for method: SAML
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.514886 d Authentication   Authenticate.cc(00499) : exception during authentication: ERROR [CODE-4230] Invalid assertion: Unable to verify XML signature(StatusCode: , StatusMessage: )
exception  1: no.71004230  (ptime/session/eapi/security/Authenticate.cc:480) TID: 13769
    Unable to verify XML signature(StatusCode: , StatusMessage: )
NO exception throw location recorded. Stack generation suppressed.
exception type information:
[13769]\{13769\}[42/-1] 2025-04-01 13:36:18.515007 e XSSession        XSSessionLifecycle.cpp(00303) : Assertion authentication for user  failed with reason: Unable to verify XML signature(StatusCode: , StatusMessage: ) 

SAP HANA Platform Edition 2.0

libxmlsec ERROR, Invalid assertion, XML signature , KBA , HAN-DB-SEC , SAP HANA Security & User Management , Problem