diff --git a/Frameworks/plist/src/uuid.cc b/Frameworks/plist/src/uuid.cc
index 9af21446..ac1dba36 100644
--- a/Frameworks/plist/src/uuid.cc
+++ b/Frameworks/plist/src/uuid.cc
@@ -33,7 +33,7 @@ namespace oak
 
 		if(uuid_parse(str.c_str(), data) != 0)
 		{
-			os_log_error(OS_LOG_DEFAULT, "uuid_t: error parsing ‘%{public}s’", str.c_str());
+			os_log_error(OS_LOG_DEFAULT, "uuid_t: error parsing ‘%{public}s’", str == NULL_STR ? "NULL_STR" : str.c_str());
 			uuid_clear(data);
 		}
 	}