AmazonSSMManagedInstanceCore

Last Modified

Mar 12, 2026

March 12, 2026 at 09:28 PM UTC

Version

Total Versions

Created

May 23, 2019

Actions

Subscribe to updates

Risk

High

An unrestricted escalation path, identity administration, secret reads or the power to switch off security monitoring. Read from this policy document alone: trust policies, boundaries and SCPs in your account still decide what actually succeeds. How this is assessed

High
Can read secrets
Reads Parameter Store values, SecureString included where the KMS key allows it, on any resource with no condition.
ssm:GetParameterssm:GetParameters
Use with caution: Where the holder needs only some secrets, write your own policy scoped to their ARNs or tags, and limit decryption in the KMS key policies.

Policy Document

View on GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55{
  "PolicyVersion": {
    "Document": {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Effect": "Allow",
          "Action": [
            "ssm:DescribeAssociation",
            "ssm:GetDeployablePatchSnapshotForInstance",
            "ssm:GetDocument",
            "ssm:DescribeDocument",
            "ssm:GetManifest",
            "ssm:GetParameter",
            "ssm:GetParameters",
            "ssm:ListAssociations",
            "ssm:ListInstanceAssociations",
            "ssm:PutInventory",
            "ssm:PutComplianceItems",
            "ssm:PutConfigurePackageResult",
            "ssm:UpdateAssociationStatus",
            "ssm:UpdateInstanceAssociationStatus",
            "ssm:UpdateInstanceInformation"
          ],
          "Resource": "*"
        },
        {
          "Effect": "Allow",
          "Action": [
            "ssmmessages:CreateControlChannel",
            "ssmmessages:CreateDataChannel",
            "ssmmessages:OpenControlChannel",
            "ssmmessages:OpenDataChannel"
          ],
          "Resource": "*"
        },
        {
          "Effect": "Allow",
          "Action": [
            "ec2messages:AcknowledgeMessage",
            "ec2messages:DeleteMessage",
            "ec2messages:FailMessage",
            "ec2messages:GetEndpoint",
            "ec2messages:GetMessages",
            "ec2messages:SendReply"
          ],
          "Resource": "*"
        }
      ]
    },
    "VersionId": "v2",
    "IsDefaultVersion": true,
    "CreateDate": "2019-05-23T16:54:21+00:00"
  }
}