diff --git a/components/esptool_py/espefuse.cmake b/components/esptool_py/espefuse.cmake
index d8c7d04256..8911f51942 100644
--- a/components/esptool_py/espefuse.cmake
+++ b/components/esptool_py/espefuse.cmake
@@ -12,22 +12,22 @@ function(espefuse_cmd cmd output_log)
     set(log ${SERIAL_TOOL_OUTPUT_LOG})
 
     set(prefix_str " command ===")
-    string(FIND ${log} ${prefix_str} pos)
+    string(FIND "${log}" ${prefix_str} pos)
     if(${pos} GREATER -1)
         string(LENGTH ${prefix_str} len_of_prefix_str)
         math(EXPR pos "${pos} + ${len_of_prefix_str}")
-        string(SUBSTRING ${log} ${pos} -1 final_log)
+        string(SUBSTRING "${log}" ${pos} -1 final_log)
     else()
-        set(final_log ${log})
+        set(final_log "${log}")
     endif()
 
-    set(${output_log} ${final_log} PARENT_SCOPE)
+    set(${output_log} "${final_log}" PARENT_SCOPE)
 endfunction()
 
 # Reads efuses "espefuse.py summary" and returns JSON string
 function(espefuse_get_json_summary json_str)
     espefuse_cmd("summary;--format;json" output_log)
-    set(${json_str} ${output_log} PARENT_SCOPE)
+    set(${json_str} "${output_log}" PARENT_SCOPE)
 endfunction()
 
 # See the esp-idf/docs/en/api-reference/system/efuse.rst "Get eFuses During Build".
@@ -35,13 +35,13 @@ endfunction()
 # It takes the efuse json string and returns a value of property for a given efuse name
 function(espefuse_get_efuse result efuse_json efuse_name efuse_property)
     if(${CMAKE_VERSION} VERSION_LESS "3.19.0")
-        string(REGEX MATCH "\"${efuse_name}\":[ \t\n\r]*\{[^\}]*\}" cur_efuse ${efuse_json})
-        string(REGEX MATCH "\"${efuse_property}\":[ \t\n\r]*\"?([^,\"]*)\"?," ret_value ${cur_efuse})
+        string(REGEX MATCH "\"${efuse_name}\":[ \t\n\r]*\{[^\}]*\}" cur_efuse "${efuse_json}")
+        string(REGEX MATCH "\"${efuse_property}\":[ \t\n\r]*\"?([^,\"]*)\"?," ret_value "${cur_efuse}")
         set(${result} ${CMAKE_MATCH_1} PARENT_SCOPE)
     else()
         # The JSON feature has been supported by Cmake since 3.19.0
-        string(JSON cur_efuse GET ${efuse_json} ${efuse_name})
-        string(JSON ret_value GET ${cur_efuse} ${efuse_property})
+        string(JSON cur_efuse GET "${efuse_json}" ${efuse_name})
+        string(JSON ret_value GET "${cur_efuse}" ${efuse_property})
         set(${result} ${ret_value} PARENT_SCOPE)
     endif()
 endfunction()
diff --git a/examples/system/efuse/get_efuse_summary.cmake b/examples/system/efuse/get_efuse_summary.cmake
index ecb0d2133c..26f090a880 100644
--- a/examples/system/efuse/get_efuse_summary.cmake
+++ b/examples/system/efuse/get_efuse_summary.cmake
@@ -3,6 +3,6 @@ cmake_minimum_required(VERSION 3.16)
 include(${esptool_py_dir}/espefuse.cmake)
 espefuse_get_json_summary(efuse_json)
 foreach(name ${efuse_names})
-    espefuse_get_efuse(ret_data ${efuse_json} ${name} "value")
+    espefuse_get_efuse(ret_data "${efuse_json}" ${name} "value")
     message(STATUS "FROM_CMAKE: ${name}: ${ret_data}")
 endforeach()