From f856ce5e60b1cea4b2cae5313f10b2718e6bfc74 Mon Sep 17 00:00:00 2001
From: Edward Park <ed.sh.park@gmail.com>
Date: Fri, 7 Aug 2026 21:37:24 -0700
Subject: [PATCH] fix: apply Windows state ACLs to existing descriptors

---
 fastmcp_slim/fastmcp/cli/deploy/state.py | 13 +++++++------
 tests/cli/deploy/test_credentials.py     | 14 ++++++++++----
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/fastmcp_slim/fastmcp/cli/deploy/state.py b/fastmcp_slim/fastmcp/cli/deploy/state.py
index 3ee77efcc..c037ce450 100644
--- a/fastmcp_slim/fastmcp/cli/deploy/state.py
+++ b/fastmcp_slim/fastmcp/cli/deploy/state.py
@@ -21,11 +21,15 @@ class StateFileError(RuntimeError):
 
 _WINDOWS_ACL_SCRIPT = r"""
 $ErrorActionPreference = "Stop"
-$path = $args[0]
+$path = $env:FASTMCP_STATE_PATH
 $sid = [System.Security.Principal.WindowsIdentity]::GetCurrent().User
+$acl = Get-Acl -LiteralPath $path
+$acl.SetAccessRuleProtection($true, $false)
+foreach ($existingRule in @($acl.Access)) {
+    $acl.RemoveAccessRuleSpecific($existingRule)
+}
 
 if ([System.IO.Directory]::Exists($path)) {
-    $acl = [System.Security.AccessControl.DirectorySecurity]::new()
     $inheritance = [System.Security.AccessControl.InheritanceFlags]::ContainerInherit `
         -bor [System.Security.AccessControl.InheritanceFlags]::ObjectInherit
     $rule = [System.Security.AccessControl.FileSystemAccessRule]::new(
@@ -36,7 +40,6 @@ if ([System.IO.Directory]::Exists($path)) {
         [System.Security.AccessControl.AccessControlType]::Allow
     )
 } else {
-    $acl = [System.Security.AccessControl.FileSecurity]::new()
     $rule = [System.Security.AccessControl.FileSystemAccessRule]::new(
         $sid,
         [System.Security.AccessControl.FileSystemRights]::FullControl,
@@ -44,8 +47,6 @@ if ([System.IO.Directory]::Exists($path)) {
     )
 }
 
-$acl.SetOwner($sid)
-$acl.SetAccessRuleProtection($true, $false)
 $acl.AddAccessRule($rule)
 Set-Acl -LiteralPath $path -AclObject $acl
 """
@@ -61,11 +62,11 @@ def _restrict_windows_access(path: Path) -> None:
                 "-NonInteractive",
                 "-Command",
                 _WINDOWS_ACL_SCRIPT,
-                str(path),
             ],
             check=True,
             capture_output=True,
             text=True,
+            env={**os.environ, "FASTMCP_STATE_PATH": str(path)},
         )
     except (OSError, subprocess.SubprocessError) as exc:
         raise StateFileError("Could not restrict access to CLI state") from exc
diff --git a/tests/cli/deploy/test_credentials.py b/tests/cli/deploy/test_credentials.py
index bd6f8c514..a4ea55b45 100644
--- a/tests/cli/deploy/test_credentials.py
+++ b/tests/cli/deploy/test_credentials.py
@@ -5,6 +5,7 @@ import os
 import subprocess
 import traceback
 from pathlib import Path
+from typing import cast
 
 import httpx2
 import pytest
@@ -162,9 +163,12 @@ def test_windows_acl_replaces_the_existing_access_list(
     path = tmp_path / "auth.json"
     path.write_text("{}")
     calls: list[list[str]] = []
+    state_paths: list[str] = []
 
     def run(command: list[str], **kwargs: object) -> subprocess.CompletedProcess[str]:
         calls.append(command)
+        environment = cast(dict[str, str], kwargs["env"])
+        state_paths.append(environment["FASTMCP_STATE_PATH"])
         return subprocess.CompletedProcess(command, 0, "", "")
 
     monkeypatch.setattr("fastmcp.cli.deploy.state.subprocess.run", run)
@@ -178,11 +182,13 @@ def test_windows_acl_replaces_the_existing_access_list(
             "-NonInteractive",
             "-Command",
             calls[0][5],
-            str(path),
         ]
     ]
-    assert "FileSecurity]::new()" in calls[0][5]
+    assert state_paths == [str(path)]
+    assert "$path = $env:FASTMCP_STATE_PATH" in calls[0][5]
+    assert "Get-Acl -LiteralPath $path" in calls[0][5]
     assert "SetAccessRuleProtection($true, $false)" in calls[0][5]
+    assert "RemoveAccessRuleSpecific($existingRule)" in calls[0][5]
 
 
 @pytest.mark.skipif(os.name != "nt", reason="Windows ACL inspection")
@@ -191,7 +197,7 @@ def test_windows_credential_state_allows_only_the_current_user(tmp_path: Path) -
     store = CredentialStore(state_directory)
     store.save("fmcp_secret")
     inspect_acl = r"""
-$acl = Get-Acl -LiteralPath $args[0]
+$acl = Get-Acl -LiteralPath $env:FASTMCP_STATE_PATH
 $current = [System.Security.Principal.WindowsIdentity]::GetCurrent().User.Value
 $access = @($acl.Access | ForEach-Object {
     $_.IdentityReference.Translate(
@@ -215,11 +221,11 @@ $access = @($acl.Access | ForEach-Object {
                 "-NonInteractive",
                 "-Command",
                 inspect_acl,
-                str(path),
             ],
             check=True,
             capture_output=True,
             text=True,
+            env={**os.environ, "FASTMCP_STATE_PATH": str(path)},
         )
         acl = json.loads(result.stdout)
         assert set(acl["access"]) == {acl["current"]}