diff --git a/stix2/core.py b/stix2/core.py
index 20888a8..9d51e5b 100644
--- a/stix2/core.py
+++ b/stix2/core.py
@@ -1,6 +1,7 @@
 import copy
 import importlib
 import pkgutil
+import re
 
 import stix2
 
@@ -284,12 +285,12 @@ def _collect_stix2_mappings():
         prefix = str(top_level_module.__name__) + '.'
 
         for module_loader, name, is_pkg in pkgutil.walk_packages(path=path, prefix=prefix):
-            if name.startswith('stix2.v2') and is_pkg:
+            if re.match(r'^stix2\.v2[0-9]$', name) and is_pkg:
                 mod = importlib.import_module(name, str(top_level_module.__name__))
                 STIX2_OBJ_MAPS[name.split('.')[1]] = {}
                 STIX2_OBJ_MAPS[name.split('.')[1]]['objects'] = mod.OBJ_MAP
                 STIX2_OBJ_MAPS[name.split('.')[1]]['observables'] = mod.OBJ_MAP_OBSERVABLE
                 STIX2_OBJ_MAPS[name.split('.')[1]]['observable-extensions'] = mod.EXT_MAP
-            elif name.startswith('stix2.v2') and name.endswith('.common') and is_pkg is False:
+            elif re.match(r'^stix2\.v2[0-9]\.common$', name) and is_pkg is False:
                 mod = importlib.import_module(name, str(top_level_module.__name__))
                 STIX2_OBJ_MAPS[name.split('.')[1]]['markings'] = mod.OBJ_MAP_MARKING