--- a/yum/parser.py	2016-05-11 22:13:12.315196522 +0000
+++ b/yum/parser.py	2016-05-12 00:29:34.286932445 +0000
@@ -7,7 +7,7 @@
 import Errors
 
 
-_KEYCRE = re.compile(r"\$(\w+)")
+_KEYCRE = re.compile(r"\$([a-zA-Z0-9]+)")
 
 def varReplace(raw, vars):
     '''Perform variable replacement