diff --git a/docs/environment-variables.rst b/docs/environment-variables.rst
index a549b27a4..df5cba4e6 100644
--- a/docs/environment-variables.rst
+++ b/docs/environment-variables.rst
@@ -2108,6 +2108,18 @@
      - ``CodeKeeper``
      - ``CodeKeeper``
      - MCP
+   * - ``MCP_ALLOWED_HOSTS``
+     - רשימת Host מותרים לשרת ה-MCP (CSV; תומך wildcard כמו ``*.onrender.com``). ריק = הגנת DNS-rebinding כבויה (מתאים לשרת ציבורי מוגן-טוקן).
+     - לא
+     - "" (כבוי)
+     - ``codekeeper-mcp.onrender.com``
+     - MCP
+   * - ``MCP_ALLOWED_ORIGINS``
+     - רשימת Origin מותרים לשרת ה-MCP (CSV). רלוונטי רק כשמפעילים הגנה דרך ``MCP_ALLOWED_HOSTS``.
+     - לא
+     - ""
+     - ``https://claude.ai``
+     - MCP
 
 דגלי בדיקות ופיתוח
 -------------------
diff --git a/mcp_server/server.py b/mcp_server/server.py
index 17e5cd8cc..b8b099e51 100644
--- a/mcp_server/server.py
+++ b/mcp_server/server.py
@@ -11,9 +11,11 @@
 
 from __future__ import annotations
 
+import os
 from typing import Any
 
 from mcp.server.fastmcp import Context, FastMCP
+from mcp.server.transport_security import TransportSecuritySettings
 from starlette.responses import JSONResponse
 from starlette.routing import Route
 
@@ -28,8 +30,33 @@
 )
 
 
+def _transport_security() -> TransportSecuritySettings:
+    """DNS-rebinding protection config for the Streamable-HTTP transport.
+
+    That protection targets *localhost* servers (a malicious web page tricking a
+    browser into calling 127.0.0.1). This server is public and Bearer-token
+    gated, so the default host check only blocks legitimate access behind a real
+    domain (HTTP 421 "Invalid Host header"). Default: OFF. Set MCP_ALLOWED_HOSTS
+    (comma-separated; wildcards like ``*.onrender.com`` allowed) to lock it down.
+    """
+    hosts = [h.strip() for h in os.getenv("MCP_ALLOWED_HOSTS", "").split(",") if h.strip()]
+    origins = [o.strip() for o in os.getenv("MCP_ALLOWED_ORIGINS", "").split(",") if o.strip()]
+    if hosts or origins:
+        return TransportSecuritySettings(
+            enable_dns_rebinding_protection=True,
+            allowed_hosts=hosts,
+            allowed_origins=origins,
+        )
+    return TransportSecuritySettings(enable_dns_rebinding_protection=False)
+
+
 def build_mcp(backend: Any, *, name: str = "CodeKeeper") -> FastMCP:
-    mcp: FastMCP = FastMCP(name, instructions=_INSTRUCTIONS, stateless_http=True)
+    mcp: FastMCP = FastMCP(
+        name,
+        instructions=_INSTRUCTIONS,
+        stateless_http=True,
+        transport_security=_transport_security(),
+    )
 
     @mcp.tool(description="List the user's saved code files (metadata only, no code).")
     def list_files(ctx: Context, page: int = 1, per_page: int = 50) -> dict:
diff --git a/services/config_inspector_service.py b/services/config_inspector_service.py
index 017cec181..d5a0779c8 100644
--- a/services/config_inspector_service.py
+++ b/services/config_inspector_service.py
@@ -526,6 +526,18 @@ class ConfigService:
             description="שם התצוגה של שרת ה-MCP (שם ה-Connector שמוצג ללקוח).",
             category="mcp",
         ),
+        "MCP_ALLOWED_HOSTS": ConfigDefinition(
+            key="MCP_ALLOWED_HOSTS",
+            default="",
+            description="Host מותרים לשרת ה-MCP (CSV, תומך wildcard). ריק = הגנת DNS-rebinding כבויה (מתאים לשרת ציבורי מוגן-טוקן).",
+            category="mcp",
+        ),
+        "MCP_ALLOWED_ORIGINS": ConfigDefinition(
+            key="MCP_ALLOWED_ORIGINS",
+            default="",
+            description="Origin מותרים לשרת ה-MCP (CSV). רלוונטי רק כשמפעילים הגנה דרך MCP_ALLOWED_HOSTS.",
+            category="mcp",
+        ),
 
         # --- Repo Sync Engine (Git Mirror) ---
         "REPO_NAME": ConfigDefinition(
diff --git a/tests/test_mcp_server_build.py b/tests/test_mcp_server_build.py
index ef7c56bd3..ada905968 100644
--- a/tests/test_mcp_server_build.py
+++ b/tests/test_mcp_server_build.py
@@ -57,3 +57,23 @@ def test_build_app_exposes_healthz_route():
     app = build_app(_FakeBackend(), _FakeStore())
     paths = {getattr(r, "path", None) for r in app.routes}
     assert "/healthz" in paths
+
+
+def test_transport_security_off_by_default(monkeypatch):
+    monkeypatch.delenv("MCP_ALLOWED_HOSTS", raising=False)
+    monkeypatch.delenv("MCP_ALLOWED_ORIGINS", raising=False)
+    from mcp_server.server import _transport_security
+
+    ts = _transport_security()
+    # Public token-gated server: DNS-rebinding host check must be off so a real
+    # domain (e.g. *.onrender.com) is not rejected with HTTP 421.
+    assert ts.enable_dns_rebinding_protection is False
+
+
+def test_transport_security_locks_down_via_env(monkeypatch):
+    monkeypatch.setenv("MCP_ALLOWED_HOSTS", "a.com, *.b.com")
+    from mcp_server.server import _transport_security
+
+    ts = _transport_security()
+    assert ts.enable_dns_rebinding_protection is True
+    assert ts.allowed_hosts == ["a.com", "*.b.com"]