Minimum credential set for Serverless Framework

IAMCredentials.json

{
    "Statement": [
        {
            "Action": [
                "apigateway:*",
                "cloudformation:CancelUpdateStack",
                "cloudformation:ContinueUpdateRollback",
                "cloudformation:CreateChangeSet",
                "cloudformation:CreateStack",
                "cloudformation:CreateUploadBucket",
                "cloudformation:DeleteStack",
                "cloudformation:Describe*",
                "cloudformation:EstimateTemplateCost",
                "cloudformation:ExecuteChangeSet",
                "cloudformation:Get*",
                "cloudformation:List*",
                "cloudformation:UpdateStack",
                "cloudformation:UpdateTerminationProtection",
                "cloudformation:ValidateTemplate",
                "dynamodb:CreateTable",
                "dynamodb:DeleteTable",
                "dynamodb:DescribeTable",
                "dynamodb:DescribeTimeToLive",
                "dynamodb:UpdateTimeToLive",
                "ec2:AttachInternetGateway",
                "ec2:AuthorizeSecurityGroupIngress",
                "ec2:CreateInternetGateway",
                "ec2:CreateNetworkAcl",
                "ec2:CreateNetworkAclEntry",
                "ec2:CreateRouteTable",
                "ec2:CreateSecurityGroup",
                "ec2:CreateSubnet",
                "ec2:CreateTags",
                "ec2:CreateVpc",
                "ec2:DeleteInternetGateway",
                "ec2:DeleteNetworkAcl",
                "ec2:DeleteNetworkAclEntry",
                "ec2:DeleteRouteTable",
                "ec2:DeleteSecurityGroup",
                "ec2:DeleteSubnet",
                "ec2:DeleteVpc",
                "ec2:Describe*",
                "ec2:DetachInternetGateway",
                "ec2:ModifyVpcAttribute",
                "events:DeleteRule",
                "events:DescribeRule",
                "events:ListRuleNamesByTarget",
                "events:ListRules",
                "events:ListTargetsByRule",
                "events:PutRule",
                "events:PutTargets",
                "events:RemoveTargets",
                "iam:AttachRolePolicy",
                "iam:CreateRole",
                "iam:DeleteRole",
                "iam:DeleteRolePolicy",
                "iam:DetachRolePolicy",
                "iam:GetRole",
                "iam:PassRole",
                "iam:PutRolePolicy",
                "iot:CreateTopicRule",
                "iot:DeleteTopicRule",
                "iot:DisableTopicRule",
                "iot:EnableTopicRule",
                "iot:ReplaceTopicRule",
                "kinesis:CreateStream",
                "kinesis:DeleteStream",
                "kinesis:DescribeStream",
                "lambda:*",
                "logs:CreateLogGroup",
                "logs:DeleteLogGroup",
                "logs:DescribeLogGroups",
                "logs:DescribeLogStreams",
                "logs:FilterLogEvents",
                "logs:GetLogEvents",
                "logs:PutSubscriptionFilter",
                "s3:CreateBucket",
                "s3:DeleteBucket",
                "s3:DeleteBucketPolicy",
                "s3:DeleteObject",
                "s3:DeleteObjectVersion",
                "s3:GetObject",
                "s3:GetObjectVersion",
                "s3:ListAllMyBuckets",
                "s3:ListBucket",
                "s3:PutBucketNotification",
                "s3:PutBucketPolicy",
                "s3:PutBucketTagging",
                "s3:PutBucketWebsite",
                "s3:PutEncryptionConfiguration",
                "s3:PutObject",
                "sns:CreateTopic",
                "sns:DeleteTopic",
                "sns:GetSubscriptionAttributes",
                "sns:GetTopicAttributes",
                "sns:ListSubscriptions",
                "sns:ListSubscriptionsByTopic",
                "sns:ListTopics",
                "sns:SetSubscriptionAttributes",
                "sns:SetTopicAttributes",
                "sns:Subscribe",
                "sns:Unsubscribe",
                "states:CreateStateMachine",
                "states:DeleteStateMachine"
            ],
            "Effect": "Allow",
            "Resource": "*"
        }
    ],
    "Version": "2012-10-17"
}

I also needed "logs:DeleteSubscriptionFilter" to run sls remove

So far I am using this tool to help me generate policies for my serverless projects:

https://open-sl.github.io/serverless-permission-generator/

How the policy on "Resource": "*" could be minimal? It is not. For instance, if you host other resources on the same AWS account's S3 (e.g. website) this policy will allow to do anything with it. Including uploading a backdoor or deleting your website whatsoever.

While it is very dangerous to use this policy in production, it is a good start. But it is not minimal and should be trimmed to your account situation. The title is absolutely misleading.

I need to add "states:TagResource"

@gotexis, @gargoyle, @troggy I agree completely. We use this as a Terraform template. It also could be considered a work in progress, but it does not use "*" for the Resource except where necessary. Of particular note, I have on my to-do list to add support for Cloudformation Change Sets, which was a "refactor" in Serverless version 3. This gist has ExecuteChangeSet and CreateChangeSet, but I found DeleteChangeSet is also needed. edited: Looks like DescribeChangeSet is used in the serverless code as well.

@joshuaquek thanks for that link. Wondering why that's not linked from the Serverless docs instead of this gist.

@schparky , sure no problem at all!
Hmm yeah I guess maybe its because the permission generator was not done by the same team that built the Serverless framework.

Side note - I have kind of moved on from serverless in general and now have been dabbling with unikernels instead haha - https://github.com/joshuaquek/expressjs-ops-unikernel

logs:CreateLogDelivery missed here and required in some templates

cloudformation:DeleteChangeSet was missing to make the Node.JS starter app work

Here is what I cobbled together for serverless Lambda deployments based on the helpful comments here. This could be improved by specifying your account id instead of allowing *. I was unsure which role should be allowed for iam:GetRole and ended up specifying * for that. If anyone knows which roles should be allowed there please comment.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
                "lambda:CreateFunction",
                "logs:DescribeLogGroups",
                "lambda:List*",
                "logs:DescribeLogStreams",
                "lambda:Get*",
                "logs:PutRetentionPolicy",
                "cloudformation:List*",
                "logs:CreateLogGroup",
                "cloudformation:ValidateTemplate",
                "cloudformation:Describe*",
                "cloudformation:Get*"
            ],
            "Resource": "*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "events:Put*",
                "events:Remove*",
                "events:Delete*"
            ],
            "Resource": [
                "arn:aws:events:us-east-1::event-source/*",
                "arn:aws:events:us-east-1:*:rule/*",
                "arn:aws:events:us-east-1:*:event-bus/*"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "events:DescribeRule"
            ],
            "Resource": [
                "arn:aws:events:us-east-1:*:rule/*"
            ]
        },
        {
            "Sid": "VisualEditor1",
            "Effect": "Allow",
            "Action": [
                "s3:PutAccelerateConfiguration",
                "s3:ListBucketVersions",
                "s3:CreateBucket",
                "iam:CreateRole",
                "s3:ListBucket",
                "iam:AttachRolePolicy",
                "iam:PutRolePolicy",
                "cloudformation:CreateChangeSet",
                "s3:GetBucketPolicy",
                "cloudformation:DeleteChangeSet",
                "s3:PutEncryptionConfiguration",
                "s3:GetEncryptionConfiguration",
                "iam:PassRole",
                "iam:DetachRolePolicy",
                "iam:DeleteRolePolicy",
                "s3:PutBucketAcl",
                "lambda:PutFunctionEventInvokeConfig",
                "cloudformation:UpdateStack",
                "lambda:DeleteFunctionEventInvokeConfig",
                "lambda:DeleteFunction",
                "s3:DeleteBucket",
                "cloudformation:ExecuteChangeSet",
                "iam:GetRole",
                "s3:PutBucketPublicAccessBlock",
                "lambda:InvokeFunction",
                "logs:DeleteLogGroup",
                "lambda:Update*",
                "iam:DeleteRole",
                "s3:DeleteBucketPolicy",
                "lambda:AddPermission",
                "cloudformation:CreateStack",
                "cloudformation:DeleteStack",
                "s3:PutBucketPolicy",
                "lambda:PublishVersion",
                "s3:GetBucketLocation",
                "lambda:RemovePermission",
                "lambda:CreateAlias"
            ],
            "Resource": [
                "arn:aws:s3:::*",
                "arn:aws:iam::*:role/LambdaExecutionRole",
                "arn:aws:lambda:us-east-1:*:function:*",
                "arn:aws:lambda:us-east-1:*:event-source-mapping:*",
                "arn:aws:cloudformation:us-east-1:*:stack/*/*",
                "arn:aws:logs:us-east-1:*:log-group:/aws/lambda/*:*"
            ]
        },
        {
            "Sid": "VisualEditor2",
            "Effect": "Allow",
            "Action": [
                "s3:PutObject",
                "s3:GetObject",
                "s3:DeleteObject"
            ],
            "Resource": "arn:aws:s3:::*/*"
        },
        {
            "Sid": "VisualEditor3",
            "Effect": "Allow",
            "Action": [
                "cloudformation:CreateUploadBucket",
                "cloudformation:Describe*"
            ],
            "Resource": "arn:aws:cloudformation:us-east-1:*:stack/*/*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "iam:GetRole"
            ],
            "Resource": [
                "arn:aws:iam::*:role/*"
            ]
        }
    ]
}

cloudformation:DeleteChangeSet
states:TagResource
logs:TagResource

are missing for the basic node starter .... please fix...

I wanted to share my thoughts on the serverless security project. As a developer, I am surprised to see that there is not enough official documentation available for such a critical point.
Why are there so few contributions? Could it be because everyone is granting full rights ?

Personally, I've tested the configurations provided in this gist, but unfortunately, they didn't work as expected. It appears that certain permissions are missing with the last version of serverless.

I suggest creating a minimum, tested roles file with proper permissions.

I'm currently working on my own configuration, and once it's complete, I will share it with the community.

I wanted to share my thoughts on the serverless security project. As a developer, I am surprised to see that there is not enough official documentation available for such a critical point. Why are there so few contributions? Could it be because everyone is granting full rights ?

Personally, I've tested the configurations provided in this gist, but unfortunately, they didn't work as expected. It appears that certain permissions are missing with the last version of serverless.

I suggest creating a minimum, tested roles file with proper permissions.

I'm currently working on my own configuration, and once it's complete, I will share it with the community.

Great! Can't wait for your configuration!