CVE-2020-27253

Vulnerability

The vulnerability is an improper input validation (CWE-20) in the Ingress/Egress checks routine of FactoryTalk Linx ([1]). Affected versions are 6.11 and prior. A remote, unauthenticated attacker can exploit this by sending a specially crafted network packet, leading to a denial-of-service condition ([1]).

Exploitation

An attacker does not require authentication or special privileges. The attack is performed remotely over the network by sending a malicious packet to the affected device. The advisory notes low skill level to exploit ([1]).

Impact

Successful exploitation results in a denial-of-service condition, making the device unavailable ([1]). The CVSS v3 base score is 8.6, with high availability impact and no confidentiality or integrity impact ([1]).

Mitigation

Rockwell Automation recommends upgrading to the latest version of FactoryTalk Linx ([1]). As of the advisory publication date (2020-11-26), no specific fixed version is mentioned, but users should apply any available patches. Workarounds include restricting network access to affected devices using firewalls or VPNs ([1]).