diff --git a/CMakeLists.txt b/CMakeLists.txt
index 196ff303f..ea5dc91fb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1797,7 +1797,24 @@ set_package_properties(Protobuf PROPERTIES
     PURPOSE "Used to serialize output data in a way that can be read by other applications."
     TYPE REQUIRED
 )
+if(CMAKE_VERSION VERSION_LESS 3.6)
+    if(PROTOBUF_FOUND)
+        set(Protobuf_FOUND ${PROTOBUF_FOUND})
+    endif()
+endif()
 if(Protobuf_FOUND AND CMAKE_VERSION VERSION_LESS 3.9)
+    if(PROTOBUF_INCLUDE_DIR)
+        set(Protobuf_INCLUDE_DIR ${PROTOBUF_INCLUDE_DIR})
+    endif()
+    if(PROTOBUF_LIBRARY)
+        set(Protobuf_LIBRARY ${PROTOBUF_LIBRARY})
+    endif()
+    if(PROTOBUF_PROTOC_EXECUTABLE)
+        set(Protobuf_PROTOC_EXECUTABLE ${PROTOBUF_PROTOC_EXECUTABLE})
+    endif()
+    if(PROTOBUF_PROTOC_LIBRARY)
+        set(Protobuf_PROTOC_LIBRARY ${PROTOBUF_PROTOC_EXECUTABLE})
+    endif()
     add_library(protobuf::libprotobuf SHARED IMPORTED)
     set_target_properties(protobuf::libprotobuf PROPERTIES
         IMPORTED_LINK_INTERFACE_LANGUAGES "CXX"
@@ -1811,6 +1828,20 @@ if(Protobuf_FOUND AND CMAKE_VERSION VERSION_LESS 3.9)
         IMPORTED_LOCATION "${Protobuf_PROTOC_EXECUTABLE}"
         INTERFACE_LINK_LIBRARIES "${Protobuf_PROTOC_LIBRARY}"
     )
+    if(${Protobuf_VERSION} VERSION_EQUAL "0.0.0")
+        set(_PROTOBUF_COMMON_HEADER ${Protobuf_INCLUDE_DIR}/google/protobuf/stubs/common.h)
+        set(Protobuf_VERSION "")
+        set(Protobuf_LIB_VERSION "")
+        file(STRINGS ${_PROTOBUF_COMMON_HEADER} _PROTOBUF_COMMON_H_CONTENTS REGEX "#define[ \t]+GOOGLE_PROTOBUF_VERSION[ \t]+")
+        if(_PROTOBUF_COMMON_H_CONTENTS MATCHES "#define[ \t]+GOOGLE_PROTOBUF_VERSION[ \t]+([0-9]+)")
+            set(Protobuf_LIB_VERSION "${CMAKE_MATCH_1}")
+        endif()
+        unset(_PROTOBUF_COMMON_H_CONTENTS)
+        math(EXPR _PROTOBUF_MAJOR_VERSION "${Protobuf_LIB_VERSION} / 1000000")
+        math(EXPR _PROTOBUF_MINOR_VERSION "${Protobuf_LIB_VERSION} / 1000 % 1000")
+        math(EXPR _PROTOBUF_SUBMINOR_VERSION "${Protobuf_LIB_VERSION} % 1000")
+        set(Protobuf_VERSION "${_PROTOBUF_MAJOR_VERSION}.${_PROTOBUF_MINOR_VERSION}.${_PROTOBUF_SUBMINOR_VERSION}")
+    endif()
 endif()
 if(Protobuf_FOUND AND CMAKE_CROSSCOMPILING)
     find_program(PROTOC_EXECUTABLE protoc