diff --git a/entity-framework/core/what-is-new/ef-core-3.0/breaking-changes.md b/entity-framework/core/what-is-new/ef-core-3.0/breaking-changes.md
index 746e169ba9..2a97f5d67e 100644
--- a/entity-framework/core/what-is-new/ef-core-3.0/breaking-changes.md
+++ b/entity-framework/core/what-is-new/ef-core-3.0/breaking-changes.md
@@ -44,6 +44,7 @@ Changes that we expect to only impact database providers are documented under [p
 | [Throw if multiple compatible backing fields are found](#throw-if-multiple-compatible-backing-fields-are-found) | Low      |
 | [Field-only property names should match the field name](#field-only-property-names-should-match-the-field-name) | Low      |
 | [AddDbContext/AddDbContextPool no longer call AddLogging and AddMemoryCache](#adddbc) | Low      |
+| [AddEntityFramework* adds IMemoryCache with a size limit](#adddbc) | Low      |
 | [DbContext.Entry now performs a local DetectChanges](#dbe) | Low      |
 | [String and byte array keys are not client-generated by default](#string-and-byte-array-keys-are-not-client-generated-by-default) | Low      |
 | [ILoggerFactory is now a scoped service](#ilf) | Low      |
@@ -929,7 +930,7 @@ modelBuilder
 
 **Old behavior**
 
-Before EF Core 3.0, calling `AddDbContext` or `AddDbContextPool` would also register logging and memory caching services with D.I through calls to [AddLogging](https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.loggingservicecollectionextensions.addlogging) and [AddMemoryCache](https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.memorycacheservicecollectionextensions.addmemorycache).
+Before EF Core 3.0, calling `AddDbContext` or `AddDbContextPool` would also register logging and memory caching services with DI through calls to [AddLogging](https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.loggingservicecollectionextensions.addlogging) and [AddMemoryCache](https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.memorycacheservicecollectionextensions.addmemorycache).
 
 **New behavior**
 
@@ -943,6 +944,27 @@ EF Core 3.0 does not require that these services are in the application's DI con
 
 If your application needs these services, then register them explicitly with the DI container using  [AddLogging](https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.loggingservicecollectionextensions.addlogging) or [AddMemoryCache](https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.memorycacheservicecollectionextensions.addmemorycache).
 
+### AddEntityFramework* adds IMemoryCache with a size limit
+
+[Tracking Issue #12905](https://github.com/aspnet/EntityFrameworkCore/issues/12905)
+
+**Old behavior**
+
+Before EF Core 3.0, calling `AddEntityFramework*` methods would also register memory caching services with DI without a size lime.
+
+**New behavior**
+
+Starting with EF Core 3.0, `AddEntityFramework*` will register a IMemoryCache service with a size limit. If any other services added afterwords depend on IMemoryCache they can quickly reach the default limit causing exceptions or degraded performance.
+
+**Why**
+
+Using IMemoryCache without a limit could result in uncontrolled memory usage if there is a bug in quiery cache logic or the queries are generated dynamically. Having a default limit mitigates a potential DoS attack.
+
+**Mitigations**
+
+In most cases calling `AddEntityFramework*` is not necessary if `AddDbContext` or `AddDbContextPool` is called as well. Therefore the best mitigation is to remove the `AddEntityFramework*` call.
+If your application does needs these services, then register a IMemoryCache implementation explicitly beforehand with the DI container using  [AddMemoryCache](https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.memorycacheservicecollectionextensions.addmemorycache).
+
 <a name="dbe"></a>
 
 ### DbContext.Entry now performs a local DetectChanges