diff --git a/cmd/mining/cmd/serve.go b/cmd/mining/cmd/serve.go
index 9ba0043..fdecadf 100644
--- a/cmd/mining/cmd/serve.go
+++ b/cmd/mining/cmd/serve.go
@@ -91,16 +91,15 @@ var serveCmd = &cobra.Command{
 
 				switch command {
 				case "start":
-					if len(cmdArgs) < 1 {
-						fmt.Println("Error: start command requires miner type (e.g., 'start xmrig')")
+					if len(cmdArgs) < 3 {
+						fmt.Println("Usage: start <miner_type> <pool> <wallet>")
+						fmt.Println("Example: start xmrig stratum+tcp://pool.example.com:3333 YOUR_WALLET_ADDRESS")
 					} else {
 						minerType := cmdArgs[0]
-						// Use default pool and wallet for interactive shell for simplicity
 						config := &mining.Config{
-							Pool:      "pool.hashvault.pro:443",
-							Wallet:    "888tNkZrPN6JsEgekjMnABU4TBzc2Dt29EPAvkRxbANsAnjyPbb3iQ1YBRk1UXcdRsiKc9dhwMVgN5S9cQUiyoogDavup3H", // Corrected wallet address
-							LogOutput: true,                                                                                              // Enable logging for interactive shell
-							// Add other default config values if necessary
+							Pool:      cmdArgs[1],
+							Wallet:    cmdArgs[2],
+							LogOutput: true,
 						}
 						miner, err := mgr.StartMiner(minerType, config)
 						if err != nil {
diff --git a/cmd/mining/cmd/start.go b/cmd/mining/cmd/start.go
index bc3c6f4..fa67acc 100644
--- a/cmd/mining/cmd/start.go
+++ b/cmd/mining/cmd/start.go
@@ -38,7 +38,8 @@ var startCmd = &cobra.Command{
 
 func init() {
 	rootCmd.AddCommand(startCmd)
-	startCmd.Flags().StringVarP(&minerPool, "pool", "p", "pool.hashvault.pro", "Mining pool address")
-	startCmd.Flags().StringVarP(&minerWallet, "wallet", "w", "888tNkZrPN6JsEgekjMnABU4TBzc2Dt29EPAvkRxbANsAnjyPbb3iQ1YBRk1UXcdRsiKc9dhwMVgN5S9cQUiyoogDavup3H", "Wallet address")
-	// Removed MarkFlagRequired as we now have default values
+	startCmd.Flags().StringVarP(&minerPool, "pool", "p", "", "Mining pool address (required)")
+	startCmd.Flags().StringVarP(&minerWallet, "wallet", "w", "", "Wallet address (required)")
+	_ = startCmd.MarkFlagRequired("pool")
+	_ = startCmd.MarkFlagRequired("wallet")
 }
diff --git a/pkg/mining/config_manager.go b/pkg/mining/config_manager.go
index 4e09064..2bdae8a 100644
--- a/pkg/mining/config_manager.go
+++ b/pkg/mining/config_manager.go
@@ -91,7 +91,7 @@ func SaveMinersConfig(cfg *MinersConfig) error {
 		return fmt.Errorf("failed to marshal miners config: %w", err)
 	}
 
-	if err := os.WriteFile(configPath, data, 0644); err != nil {
+	if err := os.WriteFile(configPath, data, 0600); err != nil {
 		return fmt.Errorf("failed to write miners config file: %w", err)
 	}
 	return nil
diff --git a/pkg/mining/miner.go b/pkg/mining/miner.go
index 89bbdb0..e7bcef2 100644
--- a/pkg/mining/miner.go
+++ b/pkg/mining/miner.go
@@ -510,7 +510,7 @@ func (b *BaseMiner) untar(src, dest string) error {
 
 		target := filepath.Join(dest, header.Name)
 		if !strings.HasPrefix(target, filepath.Clean(dest)+string(os.PathSeparator)) {
-			continue
+			return fmt.Errorf("%s: illegal file path in archive", header.Name)
 		}
 
 		switch header.Typeflag {
diff --git a/pkg/mining/profile_manager.go b/pkg/mining/profile_manager.go
index 67c9966..d233659 100644
--- a/pkg/mining/profile_manager.go
+++ b/pkg/mining/profile_manager.go
@@ -78,7 +78,7 @@ func (pm *ProfileManager) saveProfiles() error {
 		return err
 	}
 
-	return os.WriteFile(pm.configPath, data, 0644)
+	return os.WriteFile(pm.configPath, data, 0600)
 }
 
 // CreateProfile adds a new profile and saves it.
diff --git a/pkg/mining/service.go b/pkg/mining/service.go
index a18c470..4c34583 100644
--- a/pkg/mining/service.go
+++ b/pkg/mining/service.go
@@ -228,7 +228,7 @@ func (s *Service) updateInstallationCache() (*SystemInfo, error) {
 		return nil, fmt.Errorf("could not marshal cache data: %w", err)
 	}
 
-	if err := os.WriteFile(configPath, data, 0644); err != nil {
+	if err := os.WriteFile(configPath, data, 0600); err != nil {
 		return nil, fmt.Errorf("could not write cache file: %w", err)
 	}
 
diff --git a/pkg/mining/settings_manager.go b/pkg/mining/settings_manager.go
index 61f1fc1..480b08d 100644
--- a/pkg/mining/settings_manager.go
+++ b/pkg/mining/settings_manager.go
@@ -147,7 +147,7 @@ func (sm *SettingsManager) Save() error {
 		return err
 	}
 
-	return os.WriteFile(sm.settingsPath, data, 0644)
+	return os.WriteFile(sm.settingsPath, data, 0600)
 }
 
 // Get returns a copy of the current settings
@@ -172,7 +172,7 @@ func (sm *SettingsManager) Update(fn func(*AppSettings)) error {
 		return err
 	}
 
-	return os.WriteFile(sm.settingsPath, data, 0644)
+	return os.WriteFile(sm.settingsPath, data, 0600)
 }
 
 // UpdateWindowState saves the current window state
diff --git a/pkg/mining/ttminer_stats.go b/pkg/mining/ttminer_stats.go
index 00b40be..2d2eba3 100644
--- a/pkg/mining/ttminer_stats.go
+++ b/pkg/mining/ttminer_stats.go
@@ -9,8 +9,8 @@ import (
 
 // GetStats retrieves performance metrics from the TT-Miner API.
 func (m *TTMiner) GetStats() (*PerformanceMetrics, error) {
-	m.mu.RLock()
-	defer m.mu.RUnlock()
+	m.mu.Lock()
+	defer m.mu.Unlock()
 
 	if !m.Running {
 		return nil, errors.New("miner is not running")
diff --git a/pkg/mining/xmrig_start.go b/pkg/mining/xmrig_start.go
index 9effa6e..441759f 100644
--- a/pkg/mining/xmrig_start.go
+++ b/pkg/mining/xmrig_start.go
@@ -255,5 +255,5 @@ func (m *XMRigMiner) createConfig(config *Config) error {
 	if err != nil {
 		return err
 	}
-	return os.WriteFile(m.ConfigPath, data, 0644)
+	return os.WriteFile(m.ConfigPath, data, 0600)
 }
diff --git a/pkg/mining/xmrig_stats.go b/pkg/mining/xmrig_stats.go
index 57684bf..f2fe6e7 100644
--- a/pkg/mining/xmrig_stats.go
+++ b/pkg/mining/xmrig_stats.go
@@ -9,8 +9,8 @@ import (
 
 // GetStats retrieves the performance statistics from the running XMRig miner.
 func (m *XMRigMiner) GetStats() (*PerformanceMetrics, error) {
-	m.mu.RLock()
-	defer m.mu.RUnlock()
+	m.mu.Lock()
+	defer m.mu.Unlock()
 
 	if !m.Running {
 		return nil, errors.New("miner is not running")