Issue #18280 caused a lot of problems for a long time. The overall road towards solution (fix in a new NuGet package 4.3.1) was less than ideal.
Let's track the post-mortem here (as initiated in https://github.com/dotnet/corefx/issues/11100#issuecomment-281827797):

High-level plan to cover:

1. How did the issue slip through into release?
   • How to prevent such situation in future?
2. Why did it take 6 months to fix?
   • Why wasn't it treated/communicated/recognized as high-impact issue earlier?
   • How to recognize and react to high-impact issues earlier in future?
3. Other concerns (e.g. overall communication)

See the writeup in https://github.com/dotnet/corefx/issues/17522#issuecomment-338418610