A vulnerability exists in the HTTP request parser in Schneider Electric's Modicon M340, Modicon Premium, Modicon Quantum PLC, BMXNOR0200 which could allow arbitrary code execution.

An authorization bypass vulnerability exists in Schneider Electric's Modicon M340, Modicon Premium, Modicon Quantum PLC, BMXNOR0200. Requests to CGI functions allow malicious users to bypass authorization.

A buffer overflow vulnerability exists in Schneider Electric's Modicon M340, Modicon Premium, Modicon Quantum PLC, BMXNOR0200. The buffer overflow vulnerability is caused by the length of the source string specified (instead of the buffer size) as the number of bytes to be copied.

A vulnerability exists in the web services to process SOAP requests in Schneider Electric's Modicon M340, Modicon Premium, Modicon Quantum PLC, BMXNOR0200 which could allow result in a buffer overflow.

Vulnerable hash algorithms exists in Schneider Electric's Modicon Premium, Modicon Quantum, Modicon M340, and BMXNOR0200 controllers in all versions of the communication modules. The algorithm used to encrypt the password is vulnerable to hash collision attacks.

A Resource Exhaustion issue was discovered in Schneider Electric Modicon M340 PLC BMXNOC0401, BMXNOE0100, BMXNOE0110, BMXNOE0110H, BMXNOR0200H, BMXP341000, BMXP342000, BMXP3420102, BMXP3420102CL, BMXP342020, BMXP342020H, BMXP342030, BMXP3420302, BMXP3420302H, and BMXP342030H. A remote attacker could send a specially crafted set of packets to the PLC causing it to freeze, requiring the operator to physically press the reset button on the PLC in order to recover.

The Schneider Electric M340 PLC modules allow remote attackers to cause a denial of service (resource consumption) via unspecified vectors. NOTE: the vendor reportedly disputes this issue because it "could not be duplicated" and "an attacker could not remotely exploit this observed behavior to deny PLC control functions.