diff --git a/packages/rpa-core/src/browser/external.ts b/packages/rpa-core/src/browser/external.ts
index 7007bb9..8b98f6a 100644
--- a/packages/rpa-core/src/browser/external.ts
+++ b/packages/rpa-core/src/browser/external.ts
@@ -1,6 +1,7 @@
 import { execFile, spawn, type ChildProcess } from "node:child_process";
 import { promisify } from "node:util";
 import { promises as fs } from "node:fs";
+import { randomUUID } from "node:crypto";
 import os from "node:os";
 import path from "node:path";
 import { RuntimeError } from "../engine/types";
@@ -214,22 +215,26 @@ export async function connectRemoteBrowser(options: ExternalRemoteOptions): Prom
 
 /** 清理占用专用 profile 的残留浏览器进程。
  *  同一 user-data-dir 已有实例时，再次启动的 Chrome 会把请求转交旧实例并立即退出（代码 0），
- *  导致「启动失败（进程已退出，代码 0）」——这些实例都是本模块之前拉起的，清理是安全的。 */
+ *  导致「启动失败（进程已退出，代码 0）」——这些实例都是本模块之前拉起的，清理是安全的。
+ *  匹配按完整 user-data-dir 路径字面量过滤（非通配），只会命中本模块自己拉起的实例。 */
 async function killStaleBrowserProcesses(browserType: ExternalBrowserType, userDataDir: string): Promise<void> {
   try {
     if (process.platform === "win32") {
       const names = browserType === "edge" ? "msedge.exe" : "chrome.exe";
-      const marker = userDataDir.replace(/'/g, "''");
+      // 单引号转义防注入；-like 用字面量路径（路径内无通配符语义字符时的精确匹配）
+      const marker = userDataDir.replace(/'/g, "''").replace(/`/g, "``").replace(/\[/g, "``[");
       const script =
         `Get-CimInstance Win32_Process -Filter "Name='${names}'" | ` +
         `Where-Object { $_.CommandLine -like '*${marker}*' } | ` +
         "ForEach-Object { Stop-Process -Id $_.ProcessId -Force -ErrorAction SilentlyContinue }";
       await execAsync("powershell.exe", ["-NoProfile", "-NonInteractive", "-Command", script], { timeout: 8000, windowsHide: true });
     } else {
+      // pkill -f 用完整 profile 路径字面量（含 rpa-studio-external 前缀），不扩大清理范围
       await execAsync("pkill", ["-f", userDataDir], { timeout: 5000 });
     }
-  } catch {
-    // 清理失败不阻塞启动：可能本来就没有残留，或权限受限
+  } catch (error) {
+    // 清理失败不阻塞启动：可能本来就没有残留，或权限受限；记 warning 供审计（整改：不再静默吞）
+    console.warn(`[browser] 清理残留 ${browserType} 进程失败（不影响启动）:`, (error as Error).message);
   }
 }
 
@@ -247,7 +252,10 @@ export async function launchExternalBrowser(options: ExternalLaunchOptions): Pro
   }
 
   const userDataDir =
-    options.userDataDir?.trim() || path.join(os.tmpdir(), `rpa-studio-external-${browserType}`);
+    options.userDataDir?.trim() ||
+    // 并发/多会话隔离（审查整改）：默认 profile 加入随机后缀，进程级唯一，
+    // 避免多个运行共用同一 profile 互相挤掉登录态与调试实例。
+    path.join(os.tmpdir(), `rpa-studio-external-${browserType}-${randomUUID().slice(0, 8)}`);
   await fs.mkdir(userDataDir, { recursive: true });
 
   const extraArgs = (options.extraArgs ?? []).filter(Boolean);
@@ -309,19 +317,30 @@ export async function launchExternalBrowser(options: ExternalLaunchOptions): Pro
     });
   }
 
+  // 就绪之后的接管链（/json/list → transport.connect）：任一步失败都必须回收自己拉起的
+  // 子进程（审查整改：此前失败路径会遗留浏览器进程）。成功路径 killOnClose=true 交由关闭逻辑。
   const base = `http://127.0.0.1:${port}`;
-  const targets = await fetchJson<CdpTargetInfo[]>(`${base}/json/list`, 5000);
-  const target = pickPageTarget(targets, "about:blank");
-  const transport = await ExternalTransport.connect(target.webSocketDebuggerUrl as string, `127.0.0.1:${port}`);
-  return {
-    transport,
-    sessionKey: `launch|${browserType}|${port}`,
-    label: `${label} (127.0.0.1:${port})`,
-    httpBase: base,
-    targetId: String(target.id ?? ""),
-    child,
-    killOnClose: true
-  };
+  try {
+    const targets = await fetchJson<CdpTargetInfo[]>(`${base}/json/list`, 5000);
+    const target = pickPageTarget(targets, "about:blank");
+    const transport = await ExternalTransport.connect(target.webSocketDebuggerUrl as string, `127.0.0.1:${port}`);
+    return {
+      transport,
+      sessionKey: `launch|${browserType}|${port}`,
+      label: `${label} (127.0.0.1:${port})`,
+      httpBase: base,
+      targetId: String(target.id ?? ""),
+      child,
+      killOnClose: true
+    };
+  } catch (error) {
+    try {
+      child.kill();
+    } catch {
+      // 进程可能已自行退出
+    }
+    throw error;
+  }
 }
 
 /** 列出调试端点上的全部页面级 target（多标签枚举用）；排除 chrome://、edge:// 内部页 */
diff --git a/packages/rpa-core/src/browser/transport.ts b/packages/rpa-core/src/browser/transport.ts
index 62e1f8f..53a6899 100644
--- a/packages/rpa-core/src/browser/transport.ts
+++ b/packages/rpa-core/src/browser/transport.ts
@@ -92,11 +92,20 @@ export class ExternalTransport implements CdpTransport {
     commandTimeoutMs = 30_000
   ): Promise<ExternalTransport> {
     const transport = new ExternalTransport(wsUrl, description, commandTimeoutMs);
-    const timeout = new Promise<never>((_, reject) =>
-      setTimeout(() => reject(new RuntimeError("browser_disconnected", `连接外部浏览器超时：${description}`)), timeoutMs)
-    );
-    await Promise.race([transport.openPromise, timeout]);
-    return transport;
+    let timer: ReturnType<typeof setTimeout> | undefined;
+    const timeout = new Promise<never>((_, reject) => {
+      timer = setTimeout(() => reject(new RuntimeError("browser_disconnected", `连接外部浏览器超时：${description}`)), timeoutMs);
+    });
+    try {
+      await Promise.race([transport.openPromise, timeout]);
+      return transport;
+    } catch (error) {
+      // 超时/失败路径必须关闭底层 WebSocket（审查整改：此前失败会泄漏挂起的 ws）
+      await transport.close().catch(() => {});
+      throw error;
+    } finally {
+      if (timer !== undefined) clearTimeout(timer);
+    }
   }
 
   get closed(): boolean {