diff --git a/src/cliproxy/proxy-target-resolver.ts b/src/cliproxy/proxy-target-resolver.ts
index e87d53ff..64778f44 100644
--- a/src/cliproxy/proxy-target-resolver.ts
+++ b/src/cliproxy/proxy-target-resolver.ts
@@ -42,10 +42,15 @@ export function getProxyTarget(): ProxyTarget {
   const config = loadCliproxyServerConfig();
 
   if (config?.remote?.enabled && config.remote?.host) {
+    const protocol = config.remote.protocol ?? 'http';
+    // Default port based on protocol if not specified
+    const defaultPort = protocol === 'https' ? 443 : 80;
+    const port = config.remote.port ?? defaultPort;
+
     return {
       host: config.remote.host,
-      port: config.remote.port ?? DEFAULT_CLIPROXY_PORT,
-      protocol: config.remote.protocol ?? 'http',
+      port,
+      protocol,
       authToken: config.remote.auth_token || undefined, // Empty string -> undefined
       isRemote: true,
     };
@@ -65,7 +70,9 @@ export function getProxyTarget(): ProxyTarget {
  * @param path Endpoint path (e.g., '/v0/management/usage')
  */
 export function buildProxyUrl(target: ProxyTarget, path: string): string {
-  return `${target.protocol}://${target.host}:${target.port}${path}`;
+  // Normalize path to ensure leading slash
+  const normalizedPath = path.startsWith('/') ? path : `/${path}`;
+  return `${target.protocol}://${target.host}:${target.port}${normalizedPath}`;
 }
 
 /**
diff --git a/src/cliproxy/remote-auth-fetcher.ts b/src/cliproxy/remote-auth-fetcher.ts
index 1c5cb01a..3f11d410 100644
--- a/src/cliproxy/remote-auth-fetcher.ts
+++ b/src/cliproxy/remote-auth-fetcher.ts
@@ -10,6 +10,9 @@ import {
   ProxyTarget,
 } from './proxy-target-resolver';
 
+/** Timeout for remote fetch requests (ms) */
+const REMOTE_FETCH_TIMEOUT_MS = 5000;
+
 /** Remote auth file from CLIProxyAPI /v0/management/auth-files */
 interface RemoteAuthFile {
   id: string;
@@ -21,11 +24,6 @@ interface RemoteAuthFile {
   source: 'file' | 'memory';
 }
 
-/** Response from CLIProxyAPI auth-files endpoint */
-interface RemoteAuthFilesResponse {
-  files: RemoteAuthFile[];
-}
-
 /** Account info for UI display */
 export interface RemoteAccountInfo {
   id: string;
@@ -39,7 +37,6 @@ export interface RemoteAuthStatus {
   provider: string;
   displayName: string;
   authenticated: boolean;
-  lastAuth: string | null;
   tokenFiles: number;
   accounts: RemoteAccountInfo[];
   defaultAccount: string | null;
@@ -78,7 +75,7 @@ export async function fetchRemoteAuthStatus(target?: ProxyTarget): Promise<Remot
   const url = buildProxyUrl(proxyTarget, '/v0/management/auth-files');
 
   const controller = new AbortController();
-  const timeoutId = setTimeout(() => controller.abort(), 5000);
+  const timeoutId = setTimeout(() => controller.abort(), REMOTE_FETCH_TIMEOUT_MS);
 
   try {
     const response = await fetch(url, {
@@ -95,8 +92,14 @@ export async function fetchRemoteAuthStatus(target?: ProxyTarget): Promise<Remot
       throw new Error(`Remote returned ${response.status}: ${response.statusText}`);
     }
 
-    const data = (await response.json()) as RemoteAuthFilesResponse;
-    return transformRemoteAuthFiles(data.files);
+    const data: unknown = await response.json();
+
+    // Validate response structure
+    if (!data || typeof data !== 'object' || !('files' in data) || !Array.isArray(data.files)) {
+      throw new Error('Invalid response format from remote auth endpoint');
+    }
+
+    return transformRemoteAuthFiles(data.files as RemoteAuthFile[]);
   } catch (error) {
     clearTimeout(timeoutId);
 
@@ -107,13 +110,19 @@ export async function fetchRemoteAuthStatus(target?: ProxyTarget): Promise<Remot
   }
 }
 
-/** Transform CLIProxyAPI auth files to CCS AuthStatus format */
+/**
+ * Transform CLIProxyAPI auth files to CCS AuthStatus format
+ * @param files Array of auth files from remote API
+ */
 function transformRemoteAuthFiles(files: RemoteAuthFile[]): RemoteAuthStatus[] {
   const byProvider = new Map<string, RemoteAuthFile[]>();
 
   for (const file of files) {
     const provider = PROVIDER_MAP[file.provider.toLowerCase()];
-    if (!provider) continue;
+    if (!provider) {
+      // Unknown provider, skip (could add logging in debug mode)
+      continue;
+    }
 
     const existing = byProvider.get(provider);
     if (existing) {
@@ -125,11 +134,11 @@ function transformRemoteAuthFiles(files: RemoteAuthFile[]): RemoteAuthStatus[] {
 
   const result: RemoteAuthStatus[] = [];
 
-  Array.from(byProvider.entries()).forEach(([provider, providerFiles]) => {
+  for (const [provider, providerFiles] of byProvider) {
     const activeFiles = providerFiles.filter((f) => f.status === 'active');
     const accounts: RemoteAccountInfo[] = providerFiles.map((f, idx) => ({
       id: f.id,
-      email: f.email || f.name,
+      email: f.email || f.name || 'Unknown',
       isDefault: idx === 0,
       status: f.status,
     }));
@@ -138,13 +147,12 @@ function transformRemoteAuthFiles(files: RemoteAuthFile[]): RemoteAuthStatus[] {
       provider,
       displayName: PROVIDER_DISPLAY_NAMES[provider] || provider,
       authenticated: activeFiles.length > 0,
-      lastAuth: null,
       tokenFiles: providerFiles.length,
       accounts,
       defaultAccount: accounts.find((a) => a.isDefault)?.id || null,
       source: 'remote',
     });
-  });
+  }
 
   return result;
 }
diff --git a/ui/src/components/cliproxy/control-panel-embed.tsx b/ui/src/components/cliproxy/control-panel-embed.tsx
index 90636e7a..2abe97f2 100644
--- a/ui/src/components/cliproxy/control-panel-embed.tsx
+++ b/ui/src/components/cliproxy/control-panel-embed.tsx
@@ -30,12 +30,19 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
   const [showLoginHint, setShowLoginHint] = useState(true);
 
   // Fetch cliproxy_server config for remote/local mode detection
-  const { data: cliproxyConfig } = useQuery<CliproxyServerConfig>({
+  const { data: cliproxyConfig, error: configError } = useQuery<CliproxyServerConfig>({
     queryKey: ['cliproxy-server-config'],
     queryFn: () => api.cliproxyServer.get(),
     staleTime: 30000, // 30 seconds
   });
 
+  // Log config fetch errors (fallback to local mode on error)
+  useEffect(() => {
+    if (configError) {
+      console.warn('[ControlPanelEmbed] Config fetch failed, using local mode:', configError);
+    }
+  }, [configError]);
+
   // Calculate URLs and settings based on remote or local mode
   const { managementUrl, checkUrl, authToken, isRemote, displayHost } = useMemo(() => {
     const remote = cliproxyConfig?.remote;
@@ -72,10 +79,12 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
 
   // Check if CLIProxy is running
   useEffect(() => {
+    const controller = new AbortController();
+
     const checkConnection = async () => {
       try {
         const response = await fetch(checkUrl, {
-          signal: AbortSignal.timeout(2000),
+          signal: controller.signal,
         });
         if (response.ok) {
           setIsConnected(true);
@@ -88,7 +97,10 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
               : 'CLIProxy returned an error'
           );
         }
-      } catch {
+      } catch (e) {
+        // Ignore abort errors (component unmounting)
+        if (e instanceof Error && e.name === 'AbortError') return;
+
         setIsConnected(false);
         setError(
           isRemote
@@ -98,7 +110,12 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
       }
     };
 
-    checkConnection();
+    // Start connection check with timeout
+    const timeoutId = setTimeout(() => controller.abort(), 2000);
+    checkConnection().finally(() => clearTimeout(timeoutId));
+
+    // Cleanup: abort fetch on unmount
+    return () => controller.abort();
   }, [checkUrl, isRemote, displayHost]);
 
   // Handle iframe load - attempt to auto-login via postMessage
@@ -112,6 +129,14 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
       try {
         // Derive apiBase from checkUrl (remove trailing slash)
         const apiBase = checkUrl.replace(/\/$/, '');
+
+        // Security: Validate iframe src matches target origin before sending credentials
+        const iframeSrc = iframeRef.current.src;
+        if (!iframeSrc.startsWith(apiBase)) {
+          console.warn('[ControlPanelEmbed] Iframe origin mismatch, skipping postMessage');
+          return;
+        }
+
         // Send credentials to iframe
         iframeRef.current.contentWindow.postMessage(
           {
@@ -121,15 +146,17 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
           },
           apiBase
         );
-      } catch {
+      } catch (e) {
         // Cross-origin restriction - expected if not same origin
-        console.debug('[ControlPanelEmbed] postMessage failed - cross-origin');
+        console.debug('[ControlPanelEmbed] postMessage failed - cross-origin:', e);
       }
     }
   }, [checkUrl, authToken]);
 
   const handleRefresh = () => {
     setIsLoading(true);
+    setError(null);
+    setIsConnected(false);
     if (iframeRef.current) {
       iframeRef.current.src = managementUrl;
     }
@@ -187,7 +214,9 @@ export function ControlPanelEmbed({ port = CLIPROXY_DEFAULT_PORT }: ControlPanel
             <span>
               Key:{' '}
               <code className="bg-blue-100 dark:bg-blue-900 px-1 rounded font-mono font-semibold">
-                {authToken || 'ccs'}
+                {authToken && authToken.length > 4
+                  ? `***${authToken.slice(-4)}`
+                  : authToken || 'ccs'}
               </code>
             </span>
             <button