Snap7 Project Security Vulnerabilities

CVE-2017-1000230

The Snap7 Server version 1.4.1 can be crashed when the ItemCount field of the ReadVar or WriteVar functions of the S7 protocol implementation in Snap7 are provided with unexpected input, thus resulting in denial of service attack.

CVE-2020-22552

The Snap7 server component in version 1.4.1, when an attacker sends a crafted packet with COTP protocol the last-data-unit flag set to No and S7 writes a var function, the Snap7 server will be crashed.