Schneider Electric Vijeo Citect 7.20 and earlier, CitectSCADA 7.20 and earlier, and PowerLogic SCADA 7.20 and earlier allow remote attackers to read arbitrary files, send HTTP requests to intranet servers, or cause a denial of service (CPU and memory consumption) via an XML document containing an external entity declaration in conjunction with an entity reference, related to an XML External Entity (XXE) issue.