diff --git a/workspace-server/internal/handlers/channels.go b/workspace-server/internal/handlers/channels.go
index 6d9008bf5..c171e6f96 100644
--- a/workspace-server/internal/handlers/channels.go
+++ b/workspace-server/internal/handlers/channels.go
@@ -67,7 +67,10 @@ func (h *ChannelHandler) List(c *gin.Context) {
 		}
 
 		var config map[string]interface{}
-		json.Unmarshal(configJSON, &config)
+		if err := json.Unmarshal(configJSON, &config); err != nil {
+			log.Printf("Channels List: json.Unmarshal(config) for channel %s: %v", id, err)
+			config = map[string]interface{}{}
+		}
 		// #319: decrypt sensitive fields first so the mask operates on
 		// plaintext (first-4 / last-4 of the real token, not the ciphertext
 		// prefix). Decrypt errors are logged but non-fatal — List must keep
@@ -86,7 +89,10 @@ func (h *ChannelHandler) List(c *gin.Context) {
 		}
 
 		var allowed []string
-		json.Unmarshal(allowedJSON, &allowed)
+		if err := json.Unmarshal(allowedJSON, &allowed); err != nil {
+			log.Printf("Channels List: json.Unmarshal(allowed) for channel %s: %v", id, err)
+			allowed = []string{}
+		}
 
 		entry := map[string]interface{}{
 			"id":            id,
@@ -104,6 +110,9 @@ func (h *ChannelHandler) List(c *gin.Context) {
 		}
 		result = append(result, entry)
 	}
+	if err := rows.Err(); err != nil {
+		log.Printf("Channels List rows.Err workspace=%s: %v", workspaceID, err)
+	}
 
 	c.JSON(http.StatusOK, result)
 }
@@ -496,8 +505,14 @@ func (h *ChannelHandler) Webhook(c *gin.Context) {
 		if err := rows.Scan(&row.ID, &row.WorkspaceID, &row.ChannelType, &configJSON, &row.Enabled, &allowedJSON); err != nil {
 			continue
 		}
-		json.Unmarshal(configJSON, &row.Config)
-		json.Unmarshal(allowedJSON, &row.AllowedUsers)
+		if err := json.Unmarshal(configJSON, &row.Config); err != nil {
+			log.Printf("Channels webhook: json.Unmarshal(config) for row %s: %v", row.ID, err)
+			row.Config = map[string]interface{}{}
+		}
+		if err := json.Unmarshal(allowedJSON, &row.AllowedUsers); err != nil {
+			log.Printf("Channels webhook: json.Unmarshal(allowed) for row %s: %v", row.ID, err)
+			row.AllowedUsers = nil
+		}
 		if err := channels.DecryptSensitiveFields(row.Config); err != nil {
 			log.Printf("Channels: decrypt webhook row %s: %v", row.ID, err)
 			continue
@@ -514,6 +529,9 @@ func (h *ChannelHandler) Webhook(c *gin.Context) {
 			candidates = append(candidates, row)
 		}
 	}
+	if err := rows.Err(); err != nil {
+		log.Printf("Channels webhook rows.Err channelType=%s: %v", channelType, err)
+	}
 
 	if targetSlug != "" {
 		// [slug] routing — match against config username (lowercased)
diff --git a/workspace-server/internal/handlers/channels_test.go b/workspace-server/internal/handlers/channels_test.go
index 7c3454c12..8d07cd37e 100644
--- a/workspace-server/internal/handlers/channels_test.go
+++ b/workspace-server/internal/handlers/channels_test.go
@@ -116,6 +116,60 @@ func TestChannelHandler_List(t *testing.T) {
 	}
 }
 
+func TestChannelHandler_List_InvalidJSONBFallsBackToEmpty(t *testing.T) {
+	mock := setupTestDB(t)
+	handler := NewChannelHandler(newTestChannelManager())
+
+	// Valid row first
+	rows := sqlmock.NewRows([]string{
+		"id", "workspace_id", "channel_type", "channel_config", "enabled",
+		"allowed_users", "last_message_at", "message_count", "created_at", "updated_at",
+	}).AddRow(
+		"ch-valid", "ws-1", "telegram",
+		[]byte(`{"bot_token":"123:AAA","chat_id":"-100"}`),
+		true, []byte(`["user-1"]`), nil, 1, nil, nil,
+	).AddRow(
+		// Invalid JSONB — causes json.Unmarshal to fail. The handler should
+		// log the error and fall back to an empty map/array, not crash.
+		"ch-bad", "ws-1", "telegram",
+		[]byte(`not valid json at all`),
+		true, []byte(`also not json`),
+		nil, 0, nil, nil,
+	)
+	mock.ExpectQuery("SELECT .* FROM workspace_channels WHERE workspace_id").
+		WithArgs("ws-1").
+		WillReturnRows(rows)
+
+	w := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(w)
+	c.Request, _ = http.NewRequest("GET", "/workspaces/ws-1/channels", nil)
+	c.Params = gin.Params{{Key: "id", Value: "ws-1"}}
+
+	handler.List(c)
+
+	if w.Code != 200 {
+		t.Errorf("expected 200, got %d: %s", w.Code, w.Body.String())
+	}
+	var result []map[string]interface{}
+	json.Unmarshal(w.Body.Bytes(), &result)
+	// Both rows should be returned; bad row has empty config/allowed_users
+	if len(result) != 2 {
+		t.Fatalf("expected 2 channels, got %d", len(result))
+	}
+	for _, ch := range result {
+		if ch["id"] == "ch-bad" {
+			// config should be empty map, not nil/null
+			if cfg := ch["config"]; cfg == nil {
+				t.Errorf("ch-bad config should be empty map, got nil")
+			}
+			// allowed_users should be empty slice, not nil
+			if allowed := ch["allowed_users"]; allowed == nil {
+				t.Errorf("ch-bad allowed_users should be empty slice, got nil")
+			}
+		}
+	}
+}
+
 // ==================== Create ====================
 
 func TestChannelHandler_Create_Success(t *testing.T) {