diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6d1dbc9756..e4df9c60a8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Security/Plugins: add explicit `plugins.runtime.allowLegacyExec` opt-in to re-enable deprecated `runtime.system.runCommandWithTimeout` for legacy modules while keeping runtime command execution disabled by default. (#20874) Thanks @mbelinky.
 - Gateway/WebChat: block `sessions.patch` and `sessions.delete` for WebChat clients so session-store mutations stay restricted to non-WebChat operator flows. Thanks @allsmog for reporting.
 - Security/Skills: for the next npm release, reject symlinks during skill packaging to prevent external file inclusion in distributed `.skill` archives. Thanks @aether-ai-agent for reporting.
 - Security/iMessage: harden remote attachment SSH/SCP handling by requiring strict host-key verification, validating `channels.imessage.remoteHost` as `host`/`user@host`, and rejecting unsafe host tokens from config or auto-detection. Thanks @allsmog for reporting.
diff --git a/src/config/schema.help.ts b/src/config/schema.help.ts
index e618779d00..2a59c153b0 100644
--- a/src/config/schema.help.ts
+++ b/src/config/schema.help.ts
@@ -267,6 +267,8 @@ export const FIELD_HELP: Record<string, string> = {
   "plugins.allow": "Optional allowlist of plugin ids; when set, only listed plugins load.",
   "plugins.deny": "Optional denylist of plugin ids; deny wins over allowlist.",
   "plugins.load.paths": "Additional plugin files or directories to load.",
+  "plugins.runtime.allowLegacyExec":
+    "Opt-in compatibility switch to re-enable deprecated runtime.system.runCommandWithTimeout for legacy plugins (default: false).",
   "plugins.slots": "Select which plugins own exclusive slots (memory, etc.).",
   "plugins.slots.memory":
     'Select the active memory plugin by id, or "none" to disable memory plugins.',
diff --git a/src/config/schema.labels.ts b/src/config/schema.labels.ts
index 95e75b8fb5..5b27235ef4 100644
--- a/src/config/schema.labels.ts
+++ b/src/config/schema.labels.ts
@@ -306,6 +306,7 @@ export const FIELD_LABELS: Record<string, string> = {
   "plugins.allow": "Plugin Allowlist",
   "plugins.deny": "Plugin Denylist",
   "plugins.load.paths": "Plugin Load Paths",
+  "plugins.runtime.allowLegacyExec": "Allow Legacy Plugin Runtime Exec",
   "plugins.slots": "Plugin Slots",
   "plugins.slots.memory": "Memory Plugin",
   "plugins.entries": "Plugin Entries",
diff --git a/src/config/types.plugins.ts b/src/config/types.plugins.ts
index dbe51f38e3..68268683e1 100644
--- a/src/config/types.plugins.ts
+++ b/src/config/types.plugins.ts
@@ -13,6 +13,14 @@ export type PluginsLoadConfig = {
   paths?: string[];
 };
 
+export type PluginsRuntimeConfig = {
+  /**
+   * Re-enable deprecated runtime.system.runCommandWithTimeout for legacy plugins.
+   * Disabled by default for security hardening.
+   */
+  allowLegacyExec?: boolean;
+};
+
 export type PluginInstallRecord = {
   source: "npm" | "archive" | "path";
   spec?: string;
@@ -30,6 +38,7 @@ export type PluginsConfig = {
   /** Optional plugin denylist (plugin ids). */
   deny?: string[];
   load?: PluginsLoadConfig;
+  runtime?: PluginsRuntimeConfig;
   slots?: PluginSlotsConfig;
   entries?: Record<string, PluginEntryConfig>;
   installs?: Record<string, PluginInstallRecord>;
diff --git a/src/config/zod-schema.ts b/src/config/zod-schema.ts
index b47418302c..aa28f397a4 100644
--- a/src/config/zod-schema.ts
+++ b/src/config/zod-schema.ts
@@ -623,6 +623,12 @@ export const OpenClawSchema = z
           })
           .strict()
           .optional(),
+        runtime: z
+          .object({
+            allowLegacyExec: z.boolean().optional(),
+          })
+          .strict()
+          .optional(),
         slots: z
           .object({
             memory: z.string().optional(),
diff --git a/src/plugins/runtime/index.test.ts b/src/plugins/runtime/index.test.ts
index 2f72e2b934..9254ebd553 100644
--- a/src/plugins/runtime/index.test.ts
+++ b/src/plugins/runtime/index.test.ts
@@ -1,13 +1,74 @@
-import { describe, expect, it } from "vitest";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const loadConfigMock = vi.hoisted(() => vi.fn());
+const runCommandWithTimeoutMock = vi.hoisted(() => vi.fn());
+
+vi.mock("../../config/config.js", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../../config/config.js")>();
+  return {
+    ...actual,
+    loadConfig: (...args: unknown[]) => loadConfigMock(...args),
+  };
+});
+
+vi.mock("../../process/exec.js", () => ({
+  runCommandWithTimeout: (...args: unknown[]) => runCommandWithTimeoutMock(...args),
+}));
+
 import { createPluginRuntime } from "./index.js";
 
 describe("plugin runtime security hardening", () => {
-  it("blocks runtime.system.runCommandWithTimeout", async () => {
+  const blockedError =
+    "runtime.system.runCommandWithTimeout is disabled for security hardening. Use fixed-purpose runtime APIs instead.";
+
+  beforeEach(() => {
+    loadConfigMock.mockReset();
+    runCommandWithTimeoutMock.mockReset();
+    loadConfigMock.mockReturnValue({});
+  });
+
+  it("blocks runtime.system.runCommandWithTimeout by default", async () => {
     const runtime = createPluginRuntime();
     await expect(
       runtime.system.runCommandWithTimeout(["echo", "hello"], { timeoutMs: 1000 }),
-    ).rejects.toThrow(
-      "runtime.system.runCommandWithTimeout is disabled for security hardening. Use fixed-purpose runtime APIs instead.",
-    );
+    ).rejects.toThrow(blockedError);
+    expect(runCommandWithTimeoutMock).not.toHaveBeenCalled();
+  });
+
+  it("allows runtime.system.runCommandWithTimeout when explicitly opted in", async () => {
+    loadConfigMock.mockReturnValue({
+      plugins: {
+        runtime: {
+          allowLegacyExec: true,
+        },
+      },
+    });
+    const commandResult = {
+      stdout: "hello\n",
+      stderr: "",
+      code: 0,
+      signal: null,
+      killed: false,
+      termination: "exit" as const,
+    };
+    runCommandWithTimeoutMock.mockResolvedValue(commandResult);
+
+    const runtime = createPluginRuntime();
+    await expect(
+      runtime.system.runCommandWithTimeout(["echo", "hello"], { timeoutMs: 1000 }),
+    ).resolves.toEqual(commandResult);
+    expect(runCommandWithTimeoutMock).toHaveBeenCalledWith(["echo", "hello"], { timeoutMs: 1000 });
+  });
+
+  it("fails closed when config loading throws", async () => {
+    loadConfigMock.mockImplementation(() => {
+      throw new Error("config read failed");
+    });
+
+    const runtime = createPluginRuntime();
+    await expect(
+      runtime.system.runCommandWithTimeout(["echo", "hello"], { timeoutMs: 1000 }),
+    ).rejects.toThrow(blockedError);
+    expect(runCommandWithTimeoutMock).not.toHaveBeenCalled();
   });
 });
diff --git a/src/plugins/runtime/index.ts b/src/plugins/runtime/index.ts
index 58f3c52df6..2ec668fb86 100644
--- a/src/plugins/runtime/index.ts
+++ b/src/plugins/runtime/index.ts
@@ -105,6 +105,7 @@ import {
   readChannelAllowFromStore,
   upsertChannelPairingRequest,
 } from "../../pairing/pairing-store.js";
+import { runCommandWithTimeout } from "../../process/exec.js";
 import { resolveAgentRoute } from "../../routing/resolve-route.js";
 import { monitorSignalProvider } from "../../signal/index.js";
 import { probeSignal } from "../../signal/probe.js";
@@ -235,12 +236,26 @@ function loadWhatsAppActions() {
   return whatsappActionsPromise;
 }
 
-const runtimeCommandExecutionDisabled: PluginRuntime["system"]["runCommandWithTimeout"] =
-  async () => {
-    throw new Error(
-      "runtime.system.runCommandWithTimeout is disabled for security hardening. Use fixed-purpose runtime APIs instead.",
-    );
-  };
+const RUNTIME_LEGACY_EXEC_DISABLED_ERROR =
+  "runtime.system.runCommandWithTimeout is disabled for security hardening. Use fixed-purpose runtime APIs instead.";
+
+function isLegacyPluginRuntimeExecEnabled(): boolean {
+  try {
+    return loadConfig().plugins?.runtime?.allowLegacyExec === true;
+  } catch {
+    // Fail closed if config is unreadable/invalid.
+    return false;
+  }
+}
+
+const runtimeCommandExecutionGuarded: PluginRuntime["system"]["runCommandWithTimeout"] = async (
+  ...args
+) => {
+  if (!isLegacyPluginRuntimeExecEnabled()) {
+    throw new Error(RUNTIME_LEGACY_EXEC_DISABLED_ERROR);
+  }
+  return await runCommandWithTimeout(...args);
+};
 
 export function createPluginRuntime(): PluginRuntime {
   return {
@@ -251,7 +266,7 @@ export function createPluginRuntime(): PluginRuntime {
     },
     system: {
       enqueueSystemEvent,
-      runCommandWithTimeout: runtimeCommandExecutionDisabled,
+      runCommandWithTimeout: runtimeCommandExecutionGuarded,
       formatNativeDependencyHint,
     },
     media: {
diff --git a/src/plugins/runtime/types.ts b/src/plugins/runtime/types.ts
index 65ef2f856e..c0a3f7fac6 100644
--- a/src/plugins/runtime/types.ts
+++ b/src/plugins/runtime/types.ts
@@ -184,7 +184,10 @@ export type PluginRuntime = {
   };
   system: {
     enqueueSystemEvent: EnqueueSystemEvent;
-    /** @deprecated Runtime command execution is disabled at runtime for security hardening. */
+    /**
+     * @deprecated Disabled by default for security hardening.
+     * Set `plugins.runtime.allowLegacyExec: true` to opt in for legacy compatibility.
+     */
     runCommandWithTimeout: RunCommandWithTimeout;
     formatNativeDependencyHint: FormatNativeDependencyHint;
   };