diff --git a/cpu/esp32/vendor/esp-idf/nvs_flash/Makefile b/cpu/esp32/vendor/esp-idf/nvs_flash/Makefile
index f92caf4df7..41bd59f255 100644
--- a/cpu/esp32/vendor/esp-idf/nvs_flash/Makefile
+++ b/cpu/esp32/vendor/esp-idf/nvs_flash/Makefile
@@ -3,7 +3,6 @@ MODULE=esp_idf_nvs_flash
 include $(RIOTBASE)/Makefile.base
 
 CFLAGS   += -DESP_PLATFORM
-CXXFLAGS += -std=c++11
 INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/esp-idf/include/log
 INCLUDES += -I$(ESP32_SDK_DIR)/components/nvs_flash/include
 INCLUDES += -I$(ESP32_SDK_DIR)/components/spi_flash/include
diff --git a/cpu/esp8266/vendor/esp-idf/nvs_flash/src/Makefile b/cpu/esp8266/vendor/esp-idf/nvs_flash/src/Makefile
index 315ae9edaf..ef469cae59 100644
--- a/cpu/esp8266/vendor/esp-idf/nvs_flash/src/Makefile
+++ b/cpu/esp8266/vendor/esp-idf/nvs_flash/src/Makefile
@@ -3,6 +3,5 @@ MODULE=esp_idf_nvs_flash
 include $(RIOTBASE)/Makefile.base
 
 CFLAGS += -DESP_PLATFORM -DNVS_CRC_HEADER_FILE=\"crc.h\"
-CXXFLAGS += -std=c++11
 INCLUDES += -I$(ESP8266_RTOS_SDK_DIR)/components/nvs_flash/include
 INCLUDES += -I$(ESP8266_RTOS_SDK_DIR)/components/util/include