chown_items

THE RISK

High Risk

Why chown_items needs a policy

Changing ownership of files/directories is a privileged system operation that modifies access control properties. While it doesn't delete data, it can grant or revoke access to sensitive files, potentially escalating privileges or locking out legitimate users. It's not a simple write (content modification) but rather an execution of a system-level permission change.

From the tool's definition Change owner (UID) and group (GID) for multiple specified files/directories

Documented attack patterns abuse exactly the kind of access chown_items gives an agent:

POLICY

How to control chown_items

PolicyLayer is an MCP gateway — it sits between your AI agents and Filesystem, and nothing reaches the server without passing your rules. This is the rule we recommend for chown_items:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "chown_items": {
      "limits": [
        {
          "counter": "chown_items_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

chown_items stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

Create a free account and register Filesystem — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RATE-LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Filesystem tools

Destructive delete_items Delete multiple specified files or directories. Write apply_diff Apply diffs to files Write chmod_items Change permissions mode for multiple specified files/directories (POSIX-style). Write copy_items Copy multiple specified files/directories. Write create_directories Create multiple specified directories (including intermediate ones). Write move_items Move or rename multiple specified files/directories. Write replace_content Replace content within files across multiple specified paths. Write write_content Write or append content to multiple specified files (creating directories if needed). NOTE

All 13 Filesystem tools →

Execute tools on other servers

Android Forensics ADB MCP Server adb_shell_command EMBA-MCP run_emba_scan Frida Game Hacking MCP remove_breakpoint Procmon request_elevation

Go deeper

High-risk tools in Filesystem → Every high-risk tool this server exposes, in one view.
All high-risk MCP tools → Every high-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Agent sandbox → Bounding what an agent can execute and where the boundary should sit.
Least privilege for MCP → Granting agents the minimum tool surface the task needs.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about chown_items

What does the chown_items tool do? +

Change owner (UID) and group (GID) for multiple specified files/directories. It is categorised as a Execute tool in the Filesystem MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on chown_items? +

Register the Filesystem MCP server in PolicyLayer and add a rule for chown_items: 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 Filesystem. Nothing to install.

What risk level is chown_items? +

chown_items is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit chown_items? +

Yes. Add a rate_limit block to the chown_items 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.

How do I block chown_items completely? +

Set action: deny in the PolicyLayer policy for chown_items. 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.

What MCP server provides chown_items? +

chown_items is provided by the Filesystem MCP server (sylphxai/filesystem-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Filesystem tool call.

Start from Filesystem, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →