diff --git a/applications/external/evil_portal/evil_portal_app.c b/applications/external/evil_portal/evil_portal_app.c
index 903ef5087..8bfc828d9 100644
--- a/applications/external/evil_portal/evil_portal_app.c
+++ b/applications/external/evil_portal/evil_portal_app.c
@@ -27,6 +27,7 @@ Evil_PortalApp* evil_portal_app_alloc() {
 
     app->sent_reset = false;
     app->portal_logs = furi_string_alloc();
+    app->portal_logs_mutex = furi_mutex_alloc(FuriMutexTypeRecursive);
 
     app->capture_line = false;
     app->captured_line = furi_string_alloc();
@@ -81,14 +82,6 @@ Evil_PortalApp* evil_portal_app_alloc() {
 }
 
 void evil_portal_app_free(Evil_PortalApp* app) {
-    // save latest logs
-    if(furi_string_utf8_length(app->portal_logs) > 0) {
-        write_logs(app->portal_logs);
-        furi_string_free(app->portal_logs);
-    }
-
-    furi_string_free(app->captured_line);
-
     // Send reset event to dev board
     evil_portal_uart_tx((uint8_t*)(RESET_CMD), strlen(RESET_CMD));
     evil_portal_uart_tx((uint8_t*)("\n"), 1);
@@ -112,6 +105,17 @@ void evil_portal_app_free(Evil_PortalApp* app) {
 
     evil_portal_uart_free(app->uart);
 
+    // save latest logs
+    furi_mutex_acquire(app->portal_logs_mutex, FuriWaitForever);
+    if(furi_string_size(app->portal_logs) > 0) {
+        write_logs(app->portal_logs);
+        furi_string_free(app->portal_logs);
+    }
+    furi_mutex_release(app->portal_logs_mutex);
+    furi_mutex_free(app->portal_logs_mutex);
+
+    furi_string_free(app->captured_line);
+
     // Close records
     furi_record_close(RECORD_GUI);
 
diff --git a/applications/external/evil_portal/evil_portal_app_i.h b/applications/external/evil_portal/evil_portal_app_i.h
index fe4103a38..871c1cefa 100644
--- a/applications/external/evil_portal/evil_portal_app_i.h
+++ b/applications/external/evil_portal/evil_portal_app_i.h
@@ -34,6 +34,7 @@ struct Evil_PortalApp {
     SceneManager* scene_manager;
 
     FuriString* portal_logs;
+    FuriMutex* portal_logs_mutex;
 
     FuriString* text_box_store;
     size_t text_box_store_strlen;
diff --git a/applications/external/evil_portal/evil_portal_uart.c b/applications/external/evil_portal/evil_portal_uart.c
index 78a01ed0a..6437e8e8b 100644
--- a/applications/external/evil_portal/evil_portal_uart.c
+++ b/applications/external/evil_portal/evil_portal_uart.c
@@ -48,24 +48,28 @@ static int32_t uart_worker(void* context) {
                 if(uart->handle_rx_data_cb) {
                     uart->handle_rx_data_cb(uart->rx_buf, len, uart->app);
 
+                    furi_mutex_acquire(uart->app->portal_logs_mutex, FuriWaitForever);
                     if(uart->app->sent_reset == false) {
                         furi_string_cat(uart->app->portal_logs, (char*)uart->rx_buf);
                     }
 
-                    if(furi_string_utf8_length(uart->app->portal_logs) > 4000) {
+                    if(furi_string_size(uart->app->portal_logs) > 4000) {
                         write_logs(uart->app->portal_logs);
                         furi_string_reset(uart->app->portal_logs);
                     }
+                    furi_mutex_release(uart->app->portal_logs_mutex);
                 } else {
                     uart->rx_buf[len] = '\0';
+                    furi_mutex_acquire(uart->app->portal_logs_mutex, FuriWaitForever);
                     if(uart->app->sent_reset == false) {
                         furi_string_cat(uart->app->portal_logs, (char*)uart->rx_buf);
                     }
 
-                    if(furi_string_utf8_length(uart->app->portal_logs) > 4000) {
+                    if(furi_string_size(uart->app->portal_logs) > 4000) {
                         write_logs(uart->app->portal_logs);
                         furi_string_reset(uart->app->portal_logs);
                     }
+                    furi_mutex_release(uart->app->portal_logs_mutex);
                 }
             }
         }
diff --git a/applications/external/evil_portal/helpers/evil_portal_storage.c b/applications/external/evil_portal/helpers/evil_portal_storage.c
index 33bef3eab..b9704c96b 100644
--- a/applications/external/evil_portal/helpers/evil_portal_storage.c
+++ b/applications/external/evil_portal/helpers/evil_portal_storage.c
@@ -156,8 +156,7 @@ void write_logs(FuriString* portal_logs) {
     File* file = storage_file_alloc(storage);
 
     if(storage_file_open(file, seq_file_path, FSAM_WRITE, FSOM_CREATE_ALWAYS)) {
-        storage_file_write(
-            file, furi_string_get_cstr(portal_logs), furi_string_utf8_length(portal_logs));
+        storage_file_write(file, furi_string_get_cstr(portal_logs), furi_string_size(portal_logs));
     }
     storage_file_close(file);
     storage_file_free(file);
diff --git a/applications/external/evil_portal/scenes/evil_portal_scene_console_output.c b/applications/external/evil_portal/scenes/evil_portal_scene_console_output.c
index 64332eeac..70f2443fe 100644
--- a/applications/external/evil_portal/scenes/evil_portal_scene_console_output.c
+++ b/applications/external/evil_portal/scenes/evil_portal_scene_console_output.c
@@ -62,8 +62,10 @@ void evil_portal_scene_console_output_on_enter(void* context) {
             const char* help_msg = "Logs saved.\n\n";
             furi_string_cat_str(app->text_box_store, help_msg);
             app->text_box_store_strlen += strlen(help_msg);
+            furi_mutex_acquire(app->portal_logs_mutex, FuriWaitForever);
             write_logs(app->portal_logs);
             furi_string_reset(app->portal_logs);
+            furi_mutex_release(app->portal_logs_mutex);
             if(app->show_stopscan_tip) {
                 const char* msg = "Press BACK to return\n";
                 furi_string_cat_str(app->text_box_store, msg);