diff --git a/pyVoIP/SIP.py b/pyVoIP/SIP.py
index 8999cd2..a6c5aec 100644
--- a/pyVoIP/SIP.py
+++ b/pyVoIP/SIP.py
@@ -341,7 +341,7 @@ def __init__(self, data: bytes):
         self.body: Dict[str, Any] = {}
         self.authentication: Dict[str, str] = {}
         self.raw = data
-        self.auth_match = re.compile('(\w+)=("[^"]+"|[^ \t]+)')
+        self.auth_match = re.compile('(\w+)=("[^",]+"|[^ \t,]+)')
         self.parse(data)
 
     def summary(self) -> str: