3670031 - HTTP 401 error from ICM for Principal Propagation authentication

Post Principal Propagation setup between SCC and backend system, even though the connectivity is successfully working, HTTP 401 authentication error keeps on raising from dev_icm level 2 trace, similarly to below:

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[Thr 139631666906880] <<- SapSSLGetPeerInfo(sssl_hdl=7efe7003cf80)==SAP_O_K
[Thr 139631666906880]     out: subject     = "CN=*.company1.corp, O=company1.corp, C=BR"
[Thr 139631666906880] xxx xxx xx xx:xx:xx:xxx 20xx
[Thr 139631666906880]     out: issuer      = "CN=CN=*.company1.corp, O=company1.corp, C=BR"
[Thr 139631666906880]     out: cert_len    = 1482
[Thr 139631666906880]     out: csuite_name = "TLS_XXXXX_RSA_WITH_AES_128_GCM_SHA256"
[Thr 139631666906880] HttpHandleCertificate: Client certificate received: with len=xxxx, subj="CN=*.company1.corp, O=company1.corp, C=BR", issuer="CN=*.company1.corp, O=company1.corp, C=BR", cipher="TLS_E
[Thr 139631666906880] HttpIsReverseProxyTrustworthy: intermediary is trusted
[Thr 139631666906880] HTTP request (raw) [136/931/1]:
[Thr 139631666906880]   GET /sap/opu/odata/......

[Thr 139631666906880] HTTP request [136/931/1] Accept trusted forwarded certificate (received via HTTPS with trusted certificate): subject="CN=PP-username@sap.company.corp", issuer="CN=server123.sap.company.corp, C=BR"

[Thr 139631666906880] HTTP response (raw) [136/931/1]:
[Thr 139631666906880]   HTTP/1.1 401 Unauthorized
[Thr 139631666906880]   set-cookie: sap-ssolist=xxxxxxxxxxxxxxxxxxxxx; path=/; SameSite=None; secure
[Thr 139631666906880]   set-cookie: sap-usercontext=sap-client=XXX; path=/; SameSite=None; secure
[Thr 139631666906880]   content-type: text/html; charset=utf-8
[Thr 139631666906880]   content-length: 6349
[Thr 139631666906880]   sap-system: XXX
[Thr 139631666906880]   www-authenticate: Basic realm="SAP NetWeaver Application Server [xxx/xxx]"
[Thr 139631666906880]   sap-server: true
[Thr 139631666906880]   sap-icm-log-dtrace: v=0,i=,r=xxxxxxxxxxxxxxxxxx,c=xxxxxxxxxxxxxxxxxxxxx,s=1
[Thr 139631666906880]   sap-perf-fesrec: 6275.000000
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Note: Image/data in this KBA is from SAP internal systems, sample data, or demo systems, and any resemblance to real data is purely coincidental.

• SAP Cloud Connector(SCC) release independent;
• SAP AS ABAP backend system;

SAP cloud connector, CC, connector, cloud connector, SCC, principal propagation, PP, principal, propagation, email, e-mail, username, SAML, certificate, ISSUER, SUBJECT, HttpIsReverseProxyTrustworthy, HTTP 401, 401, Unauthorized, authentication, HttpHandleCertificate, SSL, SapSSLGetPeerInfo, HTTPS, CERTRULE, password, username,  , KBA , BC-MID-SCC , SAP Cloud Connector On-Demand/On-Premise Connectivity , BC-CST-IC , Internet Communication Manager , Problem