.NET 2.1.30 was released on 2021-08-19. It ships .NET Runtime 2.1.30, ASP.NET Core Runtime 2.1.30, SDK 2.1.818, 2.1.526. The official release metadata lists 3 CVEs addressed in this release. .NET 2.1 has reached end of support (2021-08-21) and no longer receives fixes.
.NET 2.2.8 was released on 2019-11-19. It ships .NET Runtime 2.2.8, ASP.NET Core Runtime 2.2.8, SDK 2.2.207, 2.2.110. .NET 2.2 has reached end of support (2019-12-23) and no longer receives fixes.
.NET 2.0.9 was released on 2018-07-10. It ships .NET Runtime 2.0.9, ASP.NET Core Runtime 2.0.9, SDK 2.1.202. The official release metadata lists 2 CVEs addressed in this release. .NET 2.0 has reached end of support (2018-10-01) and no longer receives fixes.