AWS控制台强制MFA但豁免CLI用户的IAM策略配置咨询

核心逻辑说明 #

当前策略的问题是未区分控制台临时会话和CLI长期密钥请求的请求特征，调整逻辑基于两类请求的本质差异：

• 控制台登录属于临时会话场景，请求必然携带aws:MultiFactorAuthPresent（标记是否完成MFA）和aws:TokenIssueTime（标记为临时会话）两个条件键
• CLI直接使用IAM用户长期访问密钥发起的请求，不会携带上述两个条件键

只需调整最后一条Deny语句的触发条件，让拦截规则仅对临时会话生效，即可满足需求。

调整后的完整策略 #

{
  "Version": "2012-10-17",
  "Statement": [
    {
        "Sid": "AllowViewAccountInfo",
        "Effect": "Allow",
        "Action": [
            "iam:GetAccountPasswordPolicy",
            "iam:ListVirtualMFADevices"
        ],
        "Resource": "*"
    },       
    {
        "Sid": "AllowManageOwnPasswords",
        "Effect": "Allow",
        "Action": [
            "iam:ChangePassword",
            "iam:GetUser"
        ],
        "Resource": "arn:aws:iam::*:user/${aws:username}"
    },
    {
        "Sid": "AllowManageOwnAccessKeys",
        "Effect": "Allow",
        "Action": [
            "iam:CreateAccessKey",
            "iam:DeleteAccessKey",
            "iam:ListAccessKeys",
            "iam:UpdateAccessKey"
        ],
        "Resource": "arn:aws:iam::*:user/${aws:username}"
    },
    {
        "Sid": "AllowManageOwnSigningCertificates",
        "Effect": "Allow",
        "Action": [
            "iam:DeleteSigningCertificate",
            "iam:ListSigningCertificates",
            "iam:UpdateSigningCertificate",
            "iam:UploadSigningCertificate"
        ],
        "Resource": "arn:aws:iam::*:user/${aws:username}"
    },
    {
        "Sid": "AllowManageOwnSSHPublicKeys",
        "Effect": "Allow",
        "Action": [
            "iam:DeleteSSHPublicKey",
            "iam:GetSSHPublicKey",
            "iam:ListSSHPublicKeys",
            "iam:UpdateSSHPublicKey",
            "iam:UploadSSHPublicKey"
        ],
        "Resource": "arn:aws:iam::*:user/${aws:username}"
    },
    {
        "Sid": "AllowManageOwnGitCredentials",
        "Effect": "Allow",
        "Action": [
            "iam:CreateServiceSpecificCredential",
            "iam:DeleteServiceSpecificCredential",
            "iam:ListServiceSpecificCredentials",
            "iam:ResetServiceSpecificCredential",
            "iam:UpdateServiceSpecificCredential"
        ],
        "Resource": "arn:aws:iam::*:user/${aws:username}"
    },
    {
        "Sid": "AllowManageOwnVirtualMFADevice",
        "Effect": "Allow",
        "Action": [
            "iam:CreateVirtualMFADevice",
            "iam:DeleteVirtualMFADevice"
        ],
        "Resource": "arn:aws:iam::*:mfa/${aws:username}"
    },
    {
        "Sid": "AllowManageOwnUserMFA",
        "Effect": "Allow",
        "Action": [
            "iam:DeactivateMFADevice",
            "iam:EnableMFADevice",
            "iam:ListMFADevices",
            "iam:ResyncMFADevice"
        ],
        "Resource": "arn:aws:iam::*:user/${aws:username}"
    },
    {
        "Sid": "DenyAllExceptListedIfNoMFA",
        "Effect": "Deny",
        "NotAction": [
            "iam:CreateVirtualMFADevice",
            "iam:EnableMFADevice",
            "iam:GetUser",
            "iam:ListMFADevices",
            "iam:ListVirtualMFADevices",
            "iam:ResyncMFADevice",
            "sts:GetSessionToken"
        ],
        "Resource": "*",
        "Condition": {
            "Bool": {
                "aws:MultiFactorAuthPresent": "false"
            },
            "Null": {
                "aws:TokenIssueTime": "false"
            }
        }
    }
  ]
}

调整点说明 #

仅修改了最后一条Deny语句的Condition规则：

• 新增Null条件判断aws:TokenIssueTime不为空，代表仅对临时会话（控制台登录场景）生效
• 去掉原来的BoolIfExists改为直接用Bool判断，因为临时会话必然存在aws:MultiFactorAuthPresent键，无需兼容不存在的场景

内容的提问来源于stack exchange，提问作者Norrec