AWS policy for step functions: some actions, resources, or conditions do not provide permissions

Question

I am editing a policy document to allow Lambda sending `TaskSuccess` to a step function. A statement below, although granting the right permissions, causes the warning to appear. I need advice if this is a "false positive" warning, or I am actually misconfiguring a policy document.

Statement that causes the warning:

```json
    {
      "Sid": "VisualEditor2",
      "Effect": "Allow",
      "Action": [
        "states:SendTaskSuccess",
        "states:SendTaskFailure"
      ],
      "Resource": "arn:aws:states:eu-central-1:xxxxxxxxxxxx:stateMachine:sample-waiting-step-machine"
    }
```

Warning text:

```
This policy defines some actions, resources, or conditions 
that do not provide permissions. To grant access, policies 
must have an action that has an applicable resource or condition. 
For details, choose Show remaining.
```

Once I tick "show remaining services", the following warning shows up in the table 
![warning](/media/postImages/original/IM6rduiJopShmtbIY9YG_mag)

Accepted Answer

Hi,

According to the following [AWS Github repository issue](https://github.com/aws/serverless-application-model/issues/2193), you should use `Resources: "*"` for this policy.

> According to https://docs.aws.amazon.com/step-functions/latest/dg/concept-create-iam-advanced.html, Step Function API calls to update task status require "the ARN of the activity or the token of the instance as part of the request". Since the token is provided as an input to the worker Lambda function, I think it's safe to use Resources: "*" for this policy.

AWS policy for step functions: some actions, resources, or conditions do not provide permissions

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