diff --git a/bitbake/lib/bb/data_smart.py b/bitbake/lib/bb/data_smart.py
index 1f45cd975d..07db7be97a 100644
--- a/bitbake/lib/bb/data_smart.py
+++ b/bitbake/lib/bb/data_smart.py
@@ -40,7 +40,7 @@ logger = logging.getLogger("BitBake.Data")
 
 __setvar_keyword__ = ["_append", "_prepend", "_remove"]
 __setvar_regexp__ = re.compile(r'(?P<base>.*?)(?P<keyword>_append|_prepend|_remove)(_(?P<add>[^A-Z]*))?$')
-__expand_var_regexp__ = re.compile(r"\${[^{}@\n\t :]+}")
+__expand_var_regexp__ = re.compile(r"\${[a-zA-Z0-9\-_+./~]+?}")
 __expand_python_regexp__ = re.compile(r"\${@.+?}")
 __whitespace_split__ = re.compile(r'(\s)')
 __override_regexp__ = re.compile(r'[a-z0-9]+')