OpenClaw 2026.1.21 < 2026.2.19 - Command Injection via Windows Shell Fallback in Lobster Extension

@@ -17,6 +17,7 @@ Docs: https://docs.openclaw.ai
 
 - Security/Feishu: prevent path traversal in Feishu inbound media temp-file writes by replacing key-derived temp filenames with UUID-based names. Thanks @allsmog for reporting.
 - Security/Media: harden local media ingestion against TOCTOU/symlink swap attacks by pinning reads to a single file descriptor with symlink rejection and inode/device verification in `saveMediaSource`. Thanks @dorjoos for reporting.
+- Security/Lobster (Windows): for the next npm release, remove shell-based fallback when launching Lobster wrappers (`.cmd`/`.bat`) and switch to explicit argv execution with wrapper entrypoint resolution, preventing command injection while preserving Windows wrapper compatibility. Thanks @tdjackey for reporting.
 - Agents/Streaming: keep assistant partial streaming active during reasoning streams, handle native `thinking_*` stream events consistently, dedupe mixed reasoning-end signals, and clear stale mutating tool errors after same-target retry success. (#20635) Thanks @obviyus.
 - Gateway/Auth: default unresolved gateway auth to token mode with startup auto-generation/persistence of `gateway.auth.token`, while allowing explicit `gateway.auth.mode: "none"` for intentional open loopback setups. (#20686) thanks @gumadeiras.
 - Browser/Relay: require gateway-token auth on both `/extension` and `/cdp`, and align Chrome extension setup to use a single `gateway.auth.token` input for relay authentication. Thanks @tdjackey for reporting.

@@ -3,7 +3,7 @@ import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
 import { PassThrough } from "node:stream";
-import { afterAll, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
+import { afterAll, afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
 import type { OpenClawPluginApi, OpenClawPluginToolContext } from "../../../src/plugins/types.js";
 
 const spawnState = vi.hoisted(() => ({
@@ -57,16 +57,57 @@ function fakeCtx(overrides: Partial<OpenClawPluginToolContext> = {}): OpenClawPl
   };
 }
 
+function setProcessPlatform(platform: NodeJS.Platform) {
+  Object.defineProperty(process, "platform", {
+    value: platform,
+    configurable: true,
+  });
+}
+
 describe("lobster plugin tool", () => {
   let tempDir = "";
   let lobsterBinPath = "";
+  let lobsterExePath = "";
+  const originalPlatform = Object.getOwnPropertyDescriptor(process, "platform");
+  const originalPath = process.env.PATH;
+  const originalPathAlt = process.env.Path;
+  const originalPathExt = process.env.PATHEXT;
+  const originalPathExtAlt = process.env.Pathext;
 
   beforeAll(async () => {
     ({ createLobsterTool } = await import("./lobster-tool.js"));
 
     tempDir = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-lobster-plugin-"));
     lobsterBinPath = path.join(tempDir, process.platform === "win32" ? "lobster.cmd" : "lobster");
+    lobsterExePath = path.join(tempDir, "lobster.exe");
     await fs.writeFile(lobsterBinPath, "", { encoding: "utf8", mode: 0o755 });
+    await fs.writeFile(lobsterExePath, "", { encoding: "utf8", mode: 0o755 });
+  });
+
+  afterEach(() => {
+    if (originalPlatform) {
+      Object.defineProperty(process, "platform", originalPlatform);
+    }
+    if (originalPath === undefined) {
+      delete process.env.PATH;
+    } else {
+      process.env.PATH = originalPath;
+    }
+    if (originalPathAlt === undefined) {
+      delete process.env.Path;
+    } else {
+      process.env.Path = originalPathAlt;
+    }
+    if (originalPathExt === undefined) {
+      delete process.env.PATHEXT;
+    } else {
+      process.env.PATHEXT = originalPathExt;
+    }
+    if (originalPathExtAlt === undefined) {
+      delete process.env.Pathext;
+    } else {
+      process.env.Pathext = originalPathExtAlt;
+    }
   });
 
   afterAll(async () => {
@@ -226,6 +267,156 @@ describe("lobster plugin tool", () => {
     ).rejects.toThrow(/invalid JSON/);
   });
 
+  it("runs Windows cmd shims through Node without enabling shell", async () => {
+    setProcessPlatform("win32");
+    const shimScriptPath = path.join(tempDir, "shim-dist", "lobster-cli.cjs");
+    const shimPath = path.join(tempDir, "shim", "lobster.cmd");
+    await fs.mkdir(path.dirname(shimScriptPath), { recursive: true });
+    await fs.mkdir(path.dirname(shimPath), { recursive: true });
+    await fs.writeFile(shimScriptPath, "module.exports = {};\n", "utf8");
+    await fs.writeFile(
+      shimPath,
+      `@echo off\r\n"%dp0%\\..\\shim-dist\\lobster-cli.cjs" %*\r\n`,
+      "utf8",
+    );
+    spawnState.queue.push({
+      stdout: JSON.stringify({
+        ok: true,
+        status: "ok",
+        output: [{ hello: "world" }],
+        requiresApproval: null,
+      }),
+    });
+
+    const tool = createLobsterTool(fakeApi({ pluginConfig: { lobsterPath: shimPath } }));
+    await tool.execute("call-win-shim", {
+      action: "run",
+      pipeline: "noop",
+    });
+
+    const [command, argv, options] = spawnState.spawn.mock.calls[0] ?? [];
+    expect(command).toBe(process.execPath);
+    expect(argv).toEqual([shimScriptPath, "run", "--mode", "tool", "noop"]);
+    expect(options).toMatchObject({ windowsHide: true });
+    expect(options).not.toHaveProperty("shell");
+  });
+
+  it("ignores node.exe shim entries and resolves the actual lobster script", async () => {
+    setProcessPlatform("win32");
+    const shimDir = path.join(tempDir, "shim-with-node");
+    const nodeExePath = path.join(shimDir, "node.exe");
+    const scriptPath = path.join(tempDir, "shim-dist-node", "lobster-cli.cjs");
+    const shimPath = path.join(shimDir, "lobster.cmd");
+    await fs.mkdir(path.dirname(scriptPath), { recursive: true });
+    await fs.mkdir(shimDir, { recursive: true });
+    await fs.writeFile(nodeExePath, "", "utf8");
+    await fs.writeFile(scriptPath, "module.exports = {};\n", "utf8");
+    await fs.writeFile(
+      shimPath,
+      `@echo off\r\n"%~dp0%\\node.exe" "%~dp0%\\..\\shim-dist-node\\lobster-cli.cjs" %*\r\n`,
+      "utf8",
+    );
+    spawnState.queue.push({
+      stdout: JSON.stringify({
+        ok: true,
+        status: "ok",
+        output: [{ hello: "node-first" }],
+        requiresApproval: null,
+      }),
+    });
+
+    const tool = createLobsterTool(fakeApi({ pluginConfig: { lobsterPath: shimPath } }));
+    await tool.execute("call-win-node-first", {
+      action: "run",
+      pipeline: "noop",
+    });
+
+    const [command, argv] = spawnState.spawn.mock.calls[0] ?? [];
+    expect(command).toBe(process.execPath);
+    expect(argv).toEqual([scriptPath, "run", "--mode", "tool", "noop"]);
+  });
+
+  it("resolves lobster.cmd from PATH and unwraps npm layout shim", async () => {
+    setProcessPlatform("win32");
+    const binDir = path.join(tempDir, "node_modules", ".bin");
+    const packageDir = path.join(tempDir, "node_modules", "lobster");
+    const scriptPath = path.join(packageDir, "dist", "cli.js");
+    const shimPath = path.join(binDir, "lobster.cmd");
+    await fs.mkdir(path.dirname(scriptPath), { recursive: true });
+    await fs.mkdir(binDir, { recursive: true });
+    await fs.writeFile(shimPath, "@echo off\r\n", "utf8");
+    await fs.writeFile(
+      path.join(packageDir, "package.json"),
+      JSON.stringify({ name: "lobster", version: "0.0.0", bin: { lobster: "dist/cli.js" } }),
+      "utf8",
+    );
+    await fs.writeFile(scriptPath, "module.exports = {};\n", "utf8");
+    process.env.PATHEXT = ".CMD;.EXE";
+    process.env.PATH = `${binDir};${process.env.PATH ?? ""}`;
+
+    spawnState.queue.push({
+      stdout: JSON.stringify({
+        ok: true,
+        status: "ok",
+        output: [{ hello: "path" }],
+        requiresApproval: null,
+      }),
+    });
+
+    const tool = createLobsterTool(fakeApi());
+    await tool.execute("call-win-path", {
+      action: "run",
+      pipeline: "noop",
+    });
+
+    const [command, argv] = spawnState.spawn.mock.calls[0] ?? [];
+    expect(command).toBe(process.execPath);
+    expect(argv).toEqual([scriptPath, "run", "--mode", "tool", "noop"]);
+  });
+
+  it("fails fast when cmd wrapper cannot be resolved without shell execution", async () => {
+    setProcessPlatform("win32");
+    const badShimPath = path.join(tempDir, "bad-shim", "lobster.cmd");
+    await fs.mkdir(path.dirname(badShimPath), { recursive: true });
+    await fs.writeFile(badShimPath, "@echo off\r\nREM no entrypoint\r\n", "utf8");
+
+    const tool = createLobsterTool(fakeApi({ pluginConfig: { lobsterPath: badShimPath } }));
+    await expect(
+      tool.execute("call-win-bad", {
+        action: "run",
+        pipeline: "noop",
+      }),
+    ).rejects.toThrow(/without shell execution/);
+    expect(spawnState.spawn).not.toHaveBeenCalled();
+  });
+
+  it("does not retry a failed Windows spawn with shell fallback", async () => {
+    setProcessPlatform("win32");
+    spawnState.spawn.mockReset();
+    spawnState.spawn.mockImplementationOnce(() => {
+      const child = new EventEmitter() as EventEmitter & {
+        stdout: PassThrough;
+        stderr: PassThrough;
+        kill: (signal?: string) => boolean;
+      };
+      child.stdout = new PassThrough();
+      child.stderr = new PassThrough();
+      child.kill = () => true;
+      const err = Object.assign(new Error("spawn failed"), { code: "ENOENT" });
+      setImmediate(() => child.emit("error", err));
+      return child;
+    });
+
+    const tool = createLobsterTool(fakeApi({ pluginConfig: { lobsterPath: lobsterExePath } }));
+    await expect(
+      tool.execute("call-win-no-retry", {
+        action: "run",
+        pipeline: "noop",
+      }),
+    ).rejects.toThrow(/spawn failed/);
+    expect(spawnState.spawn).toHaveBeenCalledTimes(1);
+  });
+
   it("can be gated off in sandboxed contexts", async () => {
     const api = fakeApi();
     const factoryTool = (ctx: OpenClawPluginToolContext) => {

@@ -1,7 +1,7 @@
+import { Type } from "@sinclair/typebox";
 import { spawn } from "node:child_process";
 import fs from "node:fs";
 import path from "node:path";
-import { Type } from "@sinclair/typebox";
 import type { OpenClawPluginApi } from "../../../src/plugins/types.js";
 
 type LobsterEnvelope =
@@ -84,28 +84,155 @@ function resolveCwd(cwdRaw: unknown): string {
   return resolved;
 }
 
-function isWindowsSpawnErrorThatCanUseShell(err: unknown) {
-  if (!err || typeof err !== "object") {
+function isFilePath(value: string): boolean {
+  try {
+    const stat = fs.statSync(value);
+    return stat.isFile();
+  } catch {
     return false;
   }
-  const code = (err as { code?: unknown }).code;
+}
+
+function resolveWindowsExecutablePath(execPath: string, env: NodeJS.ProcessEnv): string {
+  if (execPath.includes("/") || execPath.includes("\\") || path.isAbsolute(execPath)) {
+    return execPath;
+  }
+  const pathValue = env.PATH ?? env.Path ?? process.env.PATH ?? process.env.Path ?? "";
+  const pathEntries = pathValue
+    .split(";")
+    .map((entry) => entry.trim())
+    .filter(Boolean);
+  const hasExtension = path.extname(execPath).length > 0;
+  const pathExtRaw =
+    env.PATHEXT ??
+    env.Pathext ??
+    process.env.PATHEXT ??
+    process.env.Pathext ??
+    ".EXE;.CMD;.BAT;.COM";
+  const pathExt = hasExtension
+    ? [""]
+    : pathExtRaw
+        .split(";")
+        .map((ext) => ext.trim())
+        .filter(Boolean)
+        .map((ext) => (ext.startsWith(".") ? ext : `.${ext}`));
+  for (const dir of pathEntries) {
+    for (const ext of pathExt) {
+      for (const candidateExt of [ext, ext.toLowerCase(), ext.toUpperCase()]) {
+        const candidate = path.join(dir, `${execPath}${candidateExt}`);
+        if (isFilePath(candidate)) {
+          return candidate;
+        }
+      }
+    }
+  }
+  return execPath;
+}
 
-  // On Windows, spawning scripts discovered on PATH (e.g. lobster.cmd) can fail
-  // with EINVAL, and PATH discovery itself can fail with ENOENT when the binary
-  // is only available via PATHEXT/script wrappers.
-  return code === "EINVAL" || code === "ENOENT";
+function resolveLobsterScriptFromPackageJson(wrapperPath: string): string | null {
+  const wrapperDir = path.dirname(wrapperPath);
+  const packageDirs = [
+    // Local install: <repo>/node_modules/.bin/lobster.cmd -> ../lobster
+    path.resolve(wrapperDir, "..", "lobster"),
+    // Global npm install: <npm-prefix>/lobster.cmd -> ./node_modules/lobster
+    path.resolve(wrapperDir, "node_modules", "lobster"),
+  ];
+  for (const packageDir of packageDirs) {
+    const packageJsonPath = path.join(packageDir, "package.json");
+    if (!isFilePath(packageJsonPath)) {
+      continue;
+    }
+    try {
+      const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, "utf8")) as {
+        bin?: string | Record<string, string>;
+      };
+      const binField = packageJson.bin;
+      const scriptRel =
+        typeof binField === "string"
+          ? binField
+          : typeof binField === "object" && binField
+            ? typeof binField.lobster === "string"
+              ? binField.lobster
+              : (() => {
+                  const first = Object.values(binField).find((value) => typeof value === "string");
+                  return typeof first === "string" ? first : null;
+                })()
+            : null;
+      if (!scriptRel) {
+        continue;
+      }
+      const scriptPath = path.resolve(packageDir, scriptRel);
+      if (isFilePath(scriptPath)) {
+        return scriptPath;
+      }
+    } catch {
+      // Ignore malformed package metadata; caller will throw a guided error.
+    }
+  }
+  return null;
 }
 
-async function runLobsterSubprocessOnce(
-  params: {
-    execPath: string;
-    argv: string[];
-    cwd: string;
-    timeoutMs: number;
-    maxStdoutBytes: number;
-  },
-  useShell: boolean,
-) {
+function resolveLobsterScriptFromCmdShim(wrapperPath: string): string | null {
+  if (!isFilePath(wrapperPath)) {
+    return null;
+  }
+  try {
+    const content = fs.readFileSync(wrapperPath, "utf8");
+    // npm-style cmd shims usually reference the script as "%dp0%\\...".
+    const candidates: string[] = [];
+    const matches = content.matchAll(/"%~?dp0%\\([^"\r\n]+)"/gi);
+    for (const match of matches) {
+      const relative = match[1];
+      if (!relative) {
+        continue;
+      }
+      const normalizedRelative = relative.replace(/[\\/]+/g, path.sep);
+      const candidate = path.resolve(path.dirname(wrapperPath), normalizedRelative);
+      if (isFilePath(candidate)) {
+        candidates.push(candidate);
+      }
+    }
+    const nonNode = candidates.find((candidate) => {
+      const base = path.basename(candidate).toLowerCase();
+      return base !== "node.exe" && base !== "node";
+    });
+    if (nonNode) {
+      return nonNode;
+    }
+  } catch {
+    // Ignore unreadable shims; caller will throw a guided error.
+  }
+  return null;
+}
+
+function resolveWindowsLobsterSpawn(execPath: string, argv: string[], env: NodeJS.ProcessEnv) {
+  const resolvedExecPath = resolveWindowsExecutablePath(execPath, env);
+  const ext = path.extname(resolvedExecPath).toLowerCase();
+  if (ext !== ".cmd" && ext !== ".bat") {
+    return { command: resolvedExecPath, argv };
+  }
+  const scriptPath =
+    resolveLobsterScriptFromCmdShim(resolvedExecPath) ??
+    resolveLobsterScriptFromPackageJson(resolvedExecPath);
+  if (!scriptPath) {
+    throw new Error(
+      `lobsterPath resolved to ${path.basename(resolvedExecPath)} wrapper, but no Node entrypoint could be resolved without shell execution. Configure pluginConfig.lobsterPath to lobster.exe.`,
+    );
+  }
+  const entryExt = path.extname(scriptPath).toLowerCase();
+  if (entryExt === ".exe") {
+    return { command: scriptPath, argv, windowsHide: true };
+  }
+  return { command: process.execPath, argv: [scriptPath, ...argv], windowsHide: true };
+}
+
+async function runLobsterSubprocessOnce(params: {
+  execPath: string;
+  argv: string[];
+  cwd: string;
+  timeoutMs: number;
+  maxStdoutBytes: number;
+}) {
   const { execPath, argv, cwd } = params;
   const timeoutMs = Math.max(200, params.timeoutMs);
   const maxStdoutBytes = Math.max(1024, params.maxStdoutBytes);
@@ -115,14 +242,17 @@ async function runLobsterSubprocessOnce(
   if (nodeOptions.includes("--inspect")) {
     delete env.NODE_OPTIONS;
   }
+  const spawnTarget =
+    process.platform === "win32"
+      ? resolveWindowsLobsterSpawn(execPath, argv, env)
+      : { command: execPath, argv };
 
   return await new Promise<{ stdout: string }>((resolve, reject) => {
-    const child = spawn(execPath, argv, {
+    const child = spawn(spawnTarget.command, spawnTarget.argv, {
       cwd,
       stdio: ["ignore", "pipe", "pipe"],
       env,
-      shell: useShell,
-      windowsHide: useShell ? true : undefined,
+      windowsHide: spawnTarget.windowsHide,
     });
 
     let stdout = "";
@@ -181,14 +311,7 @@ async function runLobsterSubprocess(params: {
   timeoutMs: number;
   maxStdoutBytes: number;
 }) {
-  try {
-    return await runLobsterSubprocessOnce(params, false);
-  } catch (err) {
-    if (process.platform === "win32" && isWindowsSpawnErrorThatCanUseShell(err)) {
-      return await runLobsterSubprocessOnce(params, true);
-    }
-    throw err;
-  }
+  return await runLobsterSubprocessOnce(params);
 }
 
 function parseEnvelope(stdout: string): LobsterEnvelope {