I think he is refering to the problems caused by the September 2018 .Net security update (https://devblogs.microsoft.com/dotnet/net-framework-september-2018-security-and-quality-rollup/), which have already been resolved with the November 2018 CU (https://support.microsoft.com/en-us/help/4461511/description-of-the-security-update-for-sharepoint-foundation-2013).
So to the original question: as the updates are cumulative, this should be resolved when applying this CU.