BEA-101215 Malformed Request "null"

I am getting the following error in weblogic managed server's logs.

<Error> <HTTP> <BEA-101215> <Malformed Request "null". Request parsing failed, Code: -1>

No Application running. Just installed Managed servers and configured SSL and SAML.

As per BEA error descrption

BEA-101215: Malformed request "{0}". Request parsing failed, Code: {1} Cause: The request does not follow the pattern specified by the HTTP 1.0/1.1 specification(s). Action: Fix the client that sent the invalid request. Level: 1 Type: ERROR Impact: HTTP

But i havent installed any app and no request made.

While checking access logs - It points to other managed servers ip

<PEERIP> - <TIME> "" 400 0

Any clue / directions could help to investigate further.

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