3704081 - "PKIX path building failed" error while testing connection between SCC and backend system

Post adding a new SCC mapping, so a communication can be established with a backend system, it fails, and upon checking SCC trace (ljs_trace.log / scc_core.trc), following is perceived:

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20xx-xx-xx xx:xx:xx,xxx -0500#DEBUG#com.sap.core.connectivity.protocol.http.HttpProtocolProcessor#tunnel-client-27-3#0xc7a212e0#Opening connection to backend system <backend-host>:<backend-port>
...
...
20xx-xx-xx xx:xx:xx,xxx -0500#DEBUG#com.sap.core.connectivity.spi.processing.AbstractProtocolProcessor#tunnel-client-27-3#0xc7a212e0#Successfully opened backend connection [id: 0x7b5b7dcd, L:/<local-IP-Address>:51376 - R:<backend-host>/<backend-IP-Address>:<backend-port>]
2025-11-18 23:22:01,409 -0500#ERROR#com.sap.core.connectivity.protocol.http.handlers.HttpRequestStateHandler#tunnel-client-27-3#0xc7a212e0#Unexpected HTTP error:
com.sap.core.connectivity.protocol.http.handlers.HttpProtocolException: javax.net.ssl.SSLHandshakeException: General SSLEngine problem
    at com.sap.core.connectivity.protocol.http.handlers.HttpProtocolClientCodec.exceptionCaught(HttpProtocolClientCodec.java:80)
    at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:302)

Caused by: io.netty.handler.codec.DecoderException: javax.net.ssl.SSLHandshakeException: General SSLEngine problem
    at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:471)

Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:397)
    at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:302)

Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
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SAP Cloud Connector(SCC)

sap cloud connector, scc, cc, connector, SAP CC, sun.security.provider.certpath.SunCertPathBuilderException, pkix, jvm, backend , KBA , BC-MID-SCC , SAP Cloud Connector On-Demand/On-Premise Connectivity , Problem