How do I resolve HTTP 400 “AccessDeniedException” errors from Amazon SNS?

Resolution

1.    Update your resource's AWS Identity and Access Management (IAM) resource-based policy to allow Amazon SNS access to the resource. For more information, see Editing IAM policies in the AWS IAM user guide.

2.    Verify that your resource's IAM resource-based policy doesn’t include any Deny statements that explicitly deny your Amazon SNS topic access to the resource.
Note: AWS Lambda function IAM resource-based policies don't include the option to add an explicit deny statement.

Related information

Access management for AWS resources

Amazon SNS event destinations