system
Describe <CVE-2019-6856>.
user
What is <CVE-2019-6856>?
assistant
A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists in Modicon M580, Modicon M340, Modicon Quantum, Modicon Premium (see security notification for specific versions) which could cause a Denial of Service when writing specific physical memory blocks using Modbus TCP..