diff --git a/CMakeLists.txt b/CMakeLists.txt
index b6b271c8085..521dfdf4f02 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -433,6 +433,8 @@ endif()
 option(WITH_GTESTS "Enable GTest unit testing" OFF)
 option(WITH_OPENGL_RENDER_TESTS "Enable OpenGL render related unit testing (Experimental)" OFF)
 option(WITH_OPENGL_DRAW_TESTS "Enable OpenGL UI drawing related unit testing (Experimental)" OFF)
+set(TEST_PYTHON_EXE "" CACHE PATH "Python executable to run unit tests")
+mark_as_advanced(TEST_PYTHON_EXE)
 
 # Documentation
 if(UNIX AND NOT APPLE)
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 94b6e49181c..a3d4b2a501e 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -14,15 +14,27 @@ endif()
 # Path to Blender and Python executables for all platforms.
 if(MSVC)
   set(TEST_BLENDER_EXE ${TEST_INSTALL_DIR}/blender.exe)
-  set(TEST_PYTHON_EXE "${TEST_INSTALL_DIR}/${BLENDER_VERSION_MAJOR}.${BLENDER_VERSION_MINOR}/python/bin/python$<$<CONFIG:Debug>:_d>")
+  set(_default_test_python_exe "${TEST_INSTALL_DIR}/${BLENDER_VERSION_MAJOR}.${BLENDER_VERSION_MINOR}/python/bin/python$<$<CONFIG:Debug>:_d>")
 elseif(APPLE)
   set(TEST_BLENDER_EXE ${TEST_INSTALL_DIR}/Blender.app/Contents/MacOS/Blender)
-  set(TEST_PYTHON_EXE)
+  set(_default_test_python_exe ${PYTHON_EXECUTABLE})
 else()
   set(TEST_BLENDER_EXE ${TEST_INSTALL_DIR}/blender)
-  set(TEST_PYTHON_EXE)
+  set(_default_test_python_exe ${PYTHON_EXECUTABLE})
 endif()
 
+# The installation directory's Python is the best one to use. However, it can only be there after the install step,
+# which means that Python will never be there on a fresh system. To suit different needs, the user can pass
+# -DTEST_PYTHON_EXE=/path/to/python to CMake.
+if (NOT TEST_PYTHON_EXE)
+  set(TEST_PYTHON_EXE ${_default_test_python_exe})
+  message(STATUS "Tests: Using Python executable: ${TEST_PYTHON_EXE}")
+elseif(NOT EXISTS ${TEST_PYTHON_EXE})
+  message(FATAL_ERROR "Tests: TEST_PYTHON_EXE ${TEST_PYTHON_EXE} does not exist")
+endif()
+unset(_default_test_python_exe)
+
+
 # For testing with Valgrind
 # set(TEST_BLENDER_EXE valgrind --track-origins=yes --error-limit=no ${TEST_BLENDER_EXE})
 
diff --git a/tests/python/CMakeLists.txt b/tests/python/CMakeLists.txt
index db5d5dcf73b..753bc7c5b91 100644
--- a/tests/python/CMakeLists.txt
+++ b/tests/python/CMakeLists.txt
@@ -48,18 +48,14 @@ endfunction()
 
 # Run Python script outside Blender.
 function(add_python_test testname testscript)
-  if(MSVC)
-    add_test(
-      NAME ${testname}
-      COMMAND ${TEST_PYTHON_EXE} ${testscript} ${ARGN}
-    )
-  else()
-    add_test(
-      NAME ${testname}
-      COMMAND ${testscript} ${ARGN}
-    )
+  if(NOT TEST_PYTHON_EXE)
+    message(FATAL_ERROR "No Python configured for running tests, set TEST_PYTHON_EXE.")
   endif()
 
+  add_test(
+    NAME ${testname}
+    COMMAND ${TEST_PYTHON_EXE} ${testscript} ${ARGN}
+  )
   set_tests_properties(${testname} PROPERTIES ENVIRONMENT LSAN_OPTIONS=exitcode=0)
 endfunction()
 
diff --git a/tests/python/alembic_tests.py b/tests/python/alembic_tests.py
old mode 100755
new mode 100644
diff --git a/tests/python/cycles_render_tests.py b/tests/python/cycles_render_tests.py
old mode 100755
new mode 100644
diff --git a/tests/python/eevee_render_tests.py b/tests/python/eevee_render_tests.py
old mode 100755
new mode 100644
diff --git a/tests/python/ffmpeg_tests.py b/tests/python/ffmpeg_tests.py
old mode 100755
new mode 100644
diff --git a/tests/python/opengl_draw_tests.py b/tests/python/opengl_draw_tests.py
old mode 100755
new mode 100644
diff --git a/tests/python/workbench_render_tests.py b/tests/python/workbench_render_tests.py
old mode 100755
new mode 100644