What causes the intermittent SEC_E_BUFFER_TOO_SMALL error emanating from WinHttpSendRequest?

Question

I have a tool that executes the HTTP S POST command with the same URL with the same headers, the same message body, etc. for several iterations.

The fact that I came across the fact that for some testers each so often performs the WinHttpSendRequest () function, and the subsequent call to GetLastError () returns SEC_E_BUFFER_TOO_SMALL (0x80090321), registered here: COM error codes (security and configuration) .

This is not a registered error code for WinHttpSendRequest (), and quite extensive Googling did nothing for this.

I have four times verified that the inputs that I provide to WinHttpSendRequest () are correct and valid, and these inputs work tens of thousands of times in a row ... so far this is not the case.

I cannot provide MVCE, but in accordance with the assumptions presented here Im looking for any possible reason for returning the error code.

Answer 1

I was given an answer from someone offline and it is very interesting.

, TLS 1.2 RSA + ECDHE, 256- (2048 ) ECDHE , . (- Linux- OpenSSL, -) 25 5 256.

WinHTTP, , -, . , , Windows 7, , Windows 8 (Windows 10 ).

Microsoft Edge , 1024- 2048, , , :

TLS ServerKeyExchange 1024 DHE dh_Y 127 , Internet Explorer 11

, , OpenSSL . , , .