On .NET Core, we mishandle 1xx (includes 100-Continue) response as a final response on SocketsHttpHandler, which will constitute a cross-origin information disclosure vulnerability in case the client multiplexes requests to different origins onto a single persistent connection: the real final response to the first request will be used as a response for a different request on the same connection. (a well behaved server can cause information disclosure as well).
This issue has been addressed in the following products: .NET Core on Red Hat Enterprise Linux Via RHSA-2019:0040 https://access.redhat.com/errata/RHSA-2019:0040
References: https://github.com/dotnet/announcements/issues/94 https://github.com/dotnet/corefx/issues/34428 https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0545
Acknowledgments: Name: Microsoft