diff --git a/src/web-server/index.ts b/src/web-server/index.ts
index 6ec39e00..9aa1ae0d 100644
--- a/src/web-server/index.ts
+++ b/src/web-server/index.ts
@@ -63,6 +63,10 @@ export async function startServer(options: ServerOptions): Promise<ServerInstanc
   // Auth middleware (protects API routes when enabled)
   app.use(authMiddleware);
 
+  // CLIProxy local reverse proxy (avoids cross-origin issues in Docker)
+  const cliproxyLocalProxy = (await import('./routes/cliproxy-local-proxy')).default;
+  app.use('/api/cliproxy-local', cliproxyLocalProxy);
+
   // REST API routes (modularized)
   const { apiRoutes } = await import('./routes/index');
   app.use('/api', apiRoutes);
diff --git a/src/web-server/routes/cliproxy-local-proxy.ts b/src/web-server/routes/cliproxy-local-proxy.ts
new file mode 100644
index 00000000..a8359186
--- /dev/null
+++ b/src/web-server/routes/cliproxy-local-proxy.ts
@@ -0,0 +1,151 @@
+/**
+ * CLIProxy Local Reverse Proxy
+ *
+ * Proxies requests from the dashboard to the local CLIProxy service
+ * running on 127.0.0.1 inside the same host/container.
+ *
+ * Mounted at: /api/cliproxy-local/*  ->  http://127.0.0.1:{port}/*
+ */
+
+import http from 'http';
+import { Request, Response, Router } from 'express';
+import { CLIPROXY_DEFAULT_PORT, validatePort } from '../../cliproxy/config/port-manager';
+import { loadOrCreateUnifiedConfig } from '../../config/unified-config-loader';
+import { requireLocalAccessWhenAuthDisabled } from '../middleware/auth-middleware';
+
+export interface CliproxyLocalProxyDeps {
+  enforceAccess?: (req: Request, res: Response) => boolean;
+  request?: typeof http.request;
+  resolveTargetPort?: () => number;
+}
+
+/** Proxy request timeout in milliseconds (30 seconds) */
+const PROXY_TIMEOUT_MS = 30_000;
+
+function resolveLocalCliproxyPort(): number {
+  try {
+    const config = loadOrCreateUnifiedConfig();
+    return validatePort(config.cliproxy_server?.local?.port ?? CLIPROXY_DEFAULT_PORT);
+  } catch {
+    return CLIPROXY_DEFAULT_PORT;
+  }
+}
+
+function isJsonContentType(contentType: string | string[] | undefined): boolean {
+  const values = Array.isArray(contentType) ? contentType : [contentType];
+  return values.some((value) => value?.toLowerCase().includes('application/json') === true);
+}
+
+function buildProxyBody(req: Request): Buffer | undefined {
+  // If express.json() parsed the body (content-type is JSON and req.body is populated),
+  // re-serialize it since the original request stream was consumed by the middleware.
+  if (
+    !isJsonContentType(req.headers['content-type']) ||
+    req.body === undefined ||
+    req.body === null
+  ) {
+    return undefined;
+  }
+
+  // express.json() sets req.body to the parsed value — re-serialize for the proxy target
+  return Buffer.from(JSON.stringify(req.body));
+}
+
+function buildProxyHeaders(
+  headers: http.IncomingHttpHeaders,
+  port: number,
+  bodyBuffer?: Buffer
+): http.IncomingHttpHeaders {
+  const proxyHeaders: http.IncomingHttpHeaders = {
+    ...headers,
+    host: `127.0.0.1:${port}`,
+  };
+
+  delete proxyHeaders.connection;
+
+  if (bodyBuffer) {
+    delete proxyHeaders['transfer-encoding'];
+    proxyHeaders['content-length'] = String(bodyBuffer.length);
+  }
+
+  return proxyHeaders;
+}
+
+export function createCliproxyLocalProxyRouter(deps: CliproxyLocalProxyDeps = {}): Router {
+  const router = Router();
+  const enforceAccess =
+    deps.enforceAccess ??
+    ((req: Request, res: Response) =>
+      requireLocalAccessWhenAuthDisabled(
+        req,
+        res,
+        'CLIProxy local proxy requires localhost access when dashboard auth is disabled.'
+      ));
+  const createRequest = deps.request ?? http.request;
+  const resolveTargetPort = deps.resolveTargetPort ?? resolveLocalCliproxyPort;
+
+  router.use((req: Request, res: Response, next) => {
+    if (enforceAccess(req, res)) {
+      next();
+    }
+  });
+
+  router.all('/*', (req: Request, res: Response) => {
+    const targetPort = resolveTargetPort();
+    const targetPath = req.url || '/';
+    const bodyBuffer = buildProxyBody(req);
+
+    const proxyReq = createRequest(
+      {
+        hostname: '127.0.0.1',
+        port: targetPort,
+        path: targetPath,
+        method: req.method,
+        headers: buildProxyHeaders(req.headers, targetPort, bodyBuffer),
+        timeout: PROXY_TIMEOUT_MS,
+      },
+      (proxyRes) => {
+        res.writeHead(proxyRes.statusCode ?? 502, proxyRes.headers);
+        // Manual streaming instead of pipe() for Bun runtime compatibility
+        proxyRes.on('data', (chunk: Buffer) => res.write(chunk));
+        proxyRes.on('end', () => res.end());
+      }
+    );
+
+    proxyReq.on('timeout', () => proxyReq.destroy());
+
+    proxyReq.on('error', () => {
+      if (!res.headersSent) {
+        res.status(502).json({ error: 'CLIProxy is not reachable' });
+      }
+    });
+
+    // Clean up proxy connection when client disconnects.
+    // Only use res.on('close') — req.on('close') fires with req.destroyed=true
+    // in Bun after body consumption, which would prematurely kill the proxy.
+    res.on('close', () => {
+      if (!res.writableEnded) {
+        proxyReq.destroy();
+      }
+    });
+
+    if (bodyBuffer) {
+      proxyReq.end(bodyBuffer);
+      return;
+    }
+
+    // For methods without a body (GET, HEAD, etc.) or when express.json()
+    // has already consumed the stream, end the request immediately.
+    const hasBody = req.method !== 'GET' && req.method !== 'HEAD' && req.method !== 'OPTIONS';
+    if (!hasBody) {
+      proxyReq.end();
+      return;
+    }
+
+    req.pipe(proxyReq, { end: true });
+  });
+
+  return router;
+}
+
+export default createCliproxyLocalProxyRouter();
diff --git a/tests/unit/web-server/cliproxy-local-proxy.test.ts b/tests/unit/web-server/cliproxy-local-proxy.test.ts
new file mode 100644
index 00000000..d665731b
--- /dev/null
+++ b/tests/unit/web-server/cliproxy-local-proxy.test.ts
@@ -0,0 +1,152 @@
+import { afterEach, describe, expect, it } from 'bun:test';
+import express from 'express';
+import http from 'http';
+import type { AddressInfo } from 'net';
+
+import {
+  createCliproxyLocalProxyRouter,
+  type CliproxyLocalProxyDeps,
+} from '../../../src/web-server/routes/cliproxy-local-proxy';
+
+const servers: http.Server[] = [];
+
+async function listen(server: http.Server): Promise<number> {
+  servers.push(server);
+
+  return await new Promise<number>((resolve, reject) => {
+    server.once('error', reject);
+    server.listen(0, '127.0.0.1', () => {
+      server.off('error', reject);
+      resolve((server.address() as AddressInfo).port);
+    });
+  });
+}
+
+async function createBackendServer(
+  handler: http.RequestListener
+): Promise<{ port: number; server: http.Server }> {
+  const server = http.createServer(handler);
+  const port = await listen(server);
+  return { port, server };
+}
+
+async function createProxyServer(options: {
+  enforceAccess?: CliproxyLocalProxyDeps['enforceAccess'];
+  resolveTargetPort: () => number;
+}): Promise<{ baseUrl: string; server: http.Server }> {
+  const app = express();
+  app.use(express.json());
+  app.use(
+    '/api/cliproxy-local',
+    createCliproxyLocalProxyRouter({
+      enforceAccess: options.enforceAccess,
+      resolveTargetPort: options.resolveTargetPort,
+    })
+  );
+
+  const server = http.createServer(app);
+  const port = await listen(server);
+  return { baseUrl: `http://127.0.0.1:${port}`, server };
+}
+
+afterEach(async () => {
+  while (servers.length > 0) {
+    const server = servers.pop();
+    if (!server) {
+      continue;
+    }
+
+    // Force-close keep-alive connections so server.close() doesn't hang
+    server.closeAllConnections();
+    await new Promise<void>((resolve) => server.close(() => resolve()));
+  }
+});
+
+describe('cliproxy local proxy route', () => {
+  it('blocks requests when local-access enforcement fails', async () => {
+    let backendHit = false;
+    const backend = await createBackendServer((_req, res) => {
+      backendHit = true;
+      res.writeHead(200).end('ok');
+    });
+    const proxy = await createProxyServer({
+      resolveTargetPort: () => backend.port,
+      enforceAccess: (_req, res) => {
+        res.status(403).json({ error: 'blocked' });
+        return false;
+      },
+    });
+
+    const response = await fetch(`${proxy.baseUrl}/api/cliproxy-local/management.html`);
+
+    expect(response.status).toBe(403);
+    expect(await response.json()).toEqual({ error: 'blocked' });
+    expect(backendHit).toBe(false);
+  });
+
+  it('forwards JSON request bodies after express.json has parsed them', async () => {
+    const backend = await createBackendServer((req, res) => {
+      let body = '';
+      req.setEncoding('utf8');
+      req.on('data', (chunk) => {
+        body += chunk;
+      });
+      req.on('end', () => {
+        res.writeHead(200, { 'Content-Type': 'application/json' });
+        res.end(
+          JSON.stringify({
+            body: JSON.parse(body),
+            method: req.method,
+            path: req.url,
+          })
+        );
+      });
+    });
+    const proxy = await createProxyServer({
+      resolveTargetPort: () => backend.port,
+      enforceAccess: () => true,
+    });
+
+    const response = await fetch(`${proxy.baseUrl}/api/cliproxy-local/v0/management/test`, {
+      method: 'PATCH',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ enabled: true, ids: ['a', 'b'] }),
+    });
+
+    expect(response.status).toBe(200);
+    expect(await response.json()).toEqual({
+      body: { enabled: true, ids: ['a', 'b'] },
+      method: 'PATCH',
+      path: '/v0/management/test',
+    });
+  });
+
+  it('forwards GET requests and returns backend response', async () => {
+    const backend = await createBackendServer((_req, res) => {
+      res.writeHead(200, { 'Content-Type': 'text/html' });
+      res.end('<html>management panel</html>');
+    });
+    const proxy = await createProxyServer({
+      resolveTargetPort: () => backend.port,
+      enforceAccess: () => true,
+    });
+
+    const response = await fetch(`${proxy.baseUrl}/api/cliproxy-local/management.html`);
+
+    expect(response.status).toBe(200);
+    expect(await response.text()).toBe('<html>management panel</html>');
+  });
+
+  it('returns 502 when CLIProxy is not reachable', async () => {
+    // Use a port with nothing listening
+    const proxy = await createProxyServer({
+      resolveTargetPort: () => 19999,
+      enforceAccess: () => true,
+    });
+
+    const response = await fetch(`${proxy.baseUrl}/api/cliproxy-local/`);
+
+    expect(response.status).toBe(502);
+    expect(await response.json()).toEqual({ error: 'CLIProxy is not reachable' });
+  });
+});
diff --git a/ui/src/components/cliproxy/control-panel-embed.tsx b/ui/src/components/cliproxy/control-panel-embed.tsx
index d256c1f0..67abc74e 100644
--- a/ui/src/components/cliproxy/control-panel-embed.tsx
+++ b/ui/src/components/cliproxy/control-panel-embed.tsx
@@ -57,6 +57,7 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
   // Calculate URLs and settings based on remote or local mode
   const { managementUrl, checkUrl, authToken, isRemote, displayHost } = useMemo(() => {
     const remote = cliproxyConfig?.remote;
+    const localPort = cliproxyConfig?.local?.port ?? port;
 
     if (remote?.enabled && remote?.host) {
       const protocol = remote.protocol || 'http';
@@ -78,14 +79,15 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
       };
     }
 
-    // Local mode - use effective management secret from auth tokens API
+    // Local mode - proxy through dashboard server to avoid cross-origin/port issues
+    // (e.g., in Docker the browser cannot reach the internal CLIProxy port directly)
     const effectiveSecret = authTokens?.managementSecret?.value || 'ccs';
     return {
-      managementUrl: `http://localhost:${port}/management.html`,
-      checkUrl: `http://localhost:${port}/`,
+      managementUrl: withApiBase('/cliproxy-local/management.html'),
+      checkUrl: withApiBase('/cliproxy-local/'),
       authToken: effectiveSecret,
       isRemote: false,
-      displayHost: `localhost:${port}`,
+      displayHost: `localhost:${localPort}`,
     };
   }, [cliproxyConfig, authTokens, port]);
 
@@ -95,29 +97,50 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
   // Check if CLIProxy is running
   useEffect(() => {
     const controller = new AbortController();
+    let cancelled = false;
+
+    const updateConnectionState = (connected: boolean, nextError: string | null) => {
+      if (cancelled) return;
+      setIsConnected(connected);
+      setError(nextError);
+    };
 
     const checkConnection = async () => {
       try {
-        const response = await fetch(checkUrl, {
-          signal: controller.signal,
-        });
-        if (response.ok) {
-          setIsConnected(true);
-          setError(null);
+        if (isRemote) {
+          // Remote mode: use the test endpoint via same-origin API to avoid CORS
+          const remote = cliproxyConfig?.remote;
+          const result = await api.cliproxyServer.test({
+            host: remote?.host ?? '',
+            port: remote?.port,
+            protocol: remote?.protocol ?? 'http',
+            authToken: remote?.auth_token,
+          });
+          if (result?.reachable) {
+            updateConnectionState(true, null);
+          } else {
+            updateConnectionState(
+              false,
+              result?.error
+                ? `Remote CLIProxy at ${displayHost}: ${result.error}`
+                : `Remote CLIProxy at ${displayHost} returned an error`
+            );
+          }
         } else {
-          setIsConnected(false);
-          setError(
-            isRemote
-              ? `Remote CLIProxy at ${displayHost} returned an error`
-              : 'CLIProxy returned an error'
-          );
+          // Local mode: probe the proxied control panel root directly.
+          const response = await fetch(checkUrl, { signal: controller.signal });
+          if (response.ok) {
+            updateConnectionState(true, null);
+          } else {
+            updateConnectionState(false, 'CLIProxy returned an error');
+          }
         }
       } catch (e) {
         // Ignore abort errors (component unmounting)
         if (e instanceof Error && e.name === 'AbortError') return;
 
-        setIsConnected(false);
-        setError(
+        updateConnectionState(
+          false,
           isRemote
             ? `Remote CLIProxy at ${displayHost} is not reachable`
             : 'CLIProxy is not running'
@@ -130,8 +153,11 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
     checkConnection().finally(() => clearTimeout(timeoutId));
 
     // Cleanup: abort fetch on unmount
-    return () => controller.abort();
-  }, [checkUrl, isRemote, displayHost]);
+    return () => {
+      cancelled = true;
+      controller.abort();
+    };
+  }, [checkUrl, isRemote, displayHost, cliproxyConfig]);
 
   const postAutoLoginCredentials = useCallback(() => {
     // Auto-login can only run when iframe has loaded and authToken is available.
@@ -140,12 +166,20 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
     }
 
     try {
-      // Derive apiBase from checkUrl (remove trailing slash)
-      const apiBase = checkUrl.replace(/\/$/, '');
+      // Derive apiBase and targetOrigin from checkUrl.
+      // Local mode uses the same-origin dashboard proxy; remote mode stays absolute.
+      const apiBase = checkUrl.startsWith('/')
+        ? new URL(checkUrl.replace(/\/$/, ''), window.location.origin).href
+        : checkUrl.replace(/\/$/, '');
+      const apiBaseUrl = new URL(`${apiBase}/`);
+      const targetOrigin = apiBaseUrl.origin;
 
-      // Security: Validate iframe src matches target origin before sending credentials
-      const iframeSrc = iframeRef.current.src;
-      if (!iframeSrc.startsWith(apiBase)) {
+      // Security: Validate iframe src matches the expected origin/path before sending credentials.
+      const iframeUrl = new URL(iframeRef.current.src, window.location.origin);
+      if (
+        iframeUrl.origin !== apiBaseUrl.origin ||
+        !iframeUrl.pathname.startsWith(apiBaseUrl.pathname)
+      ) {
         console.warn('[ControlPanelEmbed] Iframe origin mismatch, skipping postMessage');
         return;
       }
@@ -157,7 +191,7 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
           apiBase,
           managementKey: authToken,
         },
-        apiBase
+        targetOrigin
       );
     } catch (e) {
       // Cross-origin restriction - expected if not same origin