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AWS AWSCloudFormation medium security documentation change

Service: AWSCloudFormation · 2025-11-19 · Security-related medium

File: AWSCloudFormation/latest/TemplateReference/aws-resource-ec2-transitgateway.md

Summary

Added documentation about required IAM permissions for transit gateway encryption and updated encryption support examples

Security assessment

Explicitly documents security-related IAM requirements for encryption configuration and adds encryption support property documentation. This helps users properly secure transit gateways through correct permissions and encryption settings.

Diff

diff --git a/AWSCloudFormation/latest/TemplateReference/aws-resource-ec2-transitgateway.md b/AWSCloudFormation/latest/TemplateReference/aws-resource-ec2-transitgateway.md
index 56725af9c..650d6c0ad 100644
--- a//AWSCloudFormation/latest/TemplateReference/aws-resource-ec2-transitgateway.md
+++ b//AWSCloudFormation/latest/TemplateReference/aws-resource-ec2-transitgateway.md
@@ -5 +5 @@ SyntaxPropertiesReturn valuesExamplesSee also
-This is the new _AWS CloudFormation Template Reference Guide_. Please update your bookmarks and links. For help getting started with CloudFormation, see the [AWS CloudFormation User Guide](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/Welcome.html).
+This is the new _CloudFormation Template Reference Guide_. Please update your bookmarks and links. For help getting started with CloudFormation, see the [AWS CloudFormation User Guide](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/Welcome.html).
@@ -18,0 +19,2 @@ When you create a transit gateway, we create a default transit gateway route tab
+To create a transit gateway with `EncryptionSupport` enabled through CloudFormation, you will need the `ec2:ModifyTransitGateway` Identity and Access Management (IAM) permission. For more information, see `ModifyTransitGateway` in [ Actions, resources, and condition keys for Amazon EC2](https://docs.aws.amazon.com/service-authorization/latest/reference/list_amazonec2.html#amazonec2-actions-as-) of the _Identify and Access Management Service Authorization Reference_.
+
@@ -21 +23 @@ When you create a transit gateway, we create a default transit gateway route tab
-To declare this entity in your AWS CloudFormation template, use the following syntax:
+To declare this entity in your CloudFormation template, use the following syntax:
@@ -263 +265 @@ For more information about using the `Fn::GetAtt` intrinsic function, see [`Fn::
-Property description not available.
+The encryption support state of the transit gateway.
@@ -286,0 +289 @@ The following example declares a transit gateway.
+          "EncryptionSupport": "disable",
@@ -309,0 +313 @@ The following example declares a transit gateway.
+          EncryptionSupport: "disable"