detach_user_policy
AI agents call detach_user_policy to permanently remove resources in AWS IoT SiteWise MCP Server — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
Detaching a policy from a user removes access permissions. While technically the policy still exists and could be re-attached, the act of detaching is a security-sensitive, potentially disruptive operation with no built-in undo. The description is empty, lowering confidence, but the name strongly implies an IAM policy removal action. Given the blast radius (could remove critical access controls), severity is high.
From the tool's definition Tool name: 'detach_user_policy' — 'detach' implies removing/unlinking a policy from a user, which is an irreversible IAM permission change that cannot be easily undone without knowing the previous state.
Attacks that exploit this kind of access
detach_user_policy. It is categorised as a Destructive tool in the AWS IoT SiteWise MCP Server MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the AWS IoT SiteWise MCP Server MCP server in PolicyLayer and add a rule for detach_user_policy: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches AWS IoT SiteWise MCP Server. Nothing to install.
detach_user_policy is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the detach_user_policy rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for detach_user_policy. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
detach_user_policy is provided by the AWS IoT SiteWise MCP Server MCP server (awslabs.aws-iot-sitewise-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.