CWE-20: Improper Input Validation vulnerability exists that could cause denial of service of engineering workstation when specific driver interface is invoked locally by an authenticated user with crafted input.

A CWE-611: Improper Restriction of XML External Entity Reference vulnerability exists that could cause unauthorized read access to the file system when a malicious configuration file is loaded on to the software by a local user. 

A successful exploit of these vulnerabilities requires the local user to load a crafted DLL file in the system directory on servers running Schneider Electric OFS v3.5 with version v7.40 of SCADA Expert Vijeo Citect/CitectSCADA, OFS v3.5 with version v7.30 of Vijeo Citect/CitectSCADA, and OFS v3.5 with version v7.20 of Vijeo Citect/CitectSCADA.. If the application attempts to open that file, the application could crash or allow the attacker to execute arbitrary code. Schneider Electric recommends vulnerable users upgrade the OFS to V3.5 and install the latest service pack (SP 6 or newer) for their associated version.

Multiple buffer overflows in the OPC Automation 2.0 Server Object ActiveX control in Schneider Electric OPC Factory Server (OFS) TLXCDSUOFS33 3.5 and earlier, TLXCDSTOFS33 3.5 and earlier, TLXCDLUOFS33 3.5 and earlier, TLXCDLTOFS33 3.5 and earlier, and TLXCDLFOFS33 3.5 and earlier allow remote attackers to cause a denial of service via long arguments to unspecified functions.

Multiple stack-based buffer overflows in ModbusDrv.exe in Schneider Electric Modbus Serial Driver 1.10 through 3.2 allow remote attackers to execute arbitrary code via a large buffer-size value in a Modbus Application Header.

Stack-based buffer overflow in the C++ sample client in Schneider Electric OPC Factory Server (OFS) TLXCDSUOFS33 - 3.35, TLXCDSTOFS33 - 3.35, TLXCDLUOFS33 - 3.35, TLXCDLTOFS33 - 3.35, and TLXCDLFOFS33 - 3.35 allows local users to gain privileges via vectors involving a malformed configuration file.

Buffer overflow in the UnitelWay Windows Device Driver, as used in Schneider Electric Unity Pro 6 and earlier, OPC Factory Server 3.34, Vijeo Citect 7.20 and earlier, Telemecanique Driver Pack 2.6 and earlier, Monitor Pro 7.6 and earlier, and PL7 Pro 4.5 and earlier, allows local users, and possibly remote attackers, to execute arbitrary code via an unspecified system parameter.