CVE-2020-5806: 
FactoryTalk Linx (RSLinx Enterprise) vulnerability analysis and mitigation

CVE-2020-5806 is a buffer overflow vulnerability discovered in Rockwell Automation's FactoryTalk Linx software, specifically affecting versions 6.10, 6.11, and 6.20. The vulnerability was identified in a .dll component of the software and was disclosed as part of a security advisory (CISA Advisory, Tenable Research).

The vulnerability is classified as a Buffer Copy Without Checking Size of Input (CWE-120) issue. An attacker-controlled memory allocation size can be passed to the C++ new operator in the CServerManager::HandleBrowseLoadIconStreamRequest function in messaging.dll. The vulnerability has been assigned a CVSS v3 base score of 6.2, with the vector string (AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) (CISA Advisory).

When exploited, this vulnerability could allow a local, unauthenticated attacker to send a malicious packet resulting in the termination of RSLinxNG.exe, causing a denial-of-service condition (CISA Advisory).

Rockwell Automation has released patches to address this vulnerability. Users are advised to update to the latest version of the software. Additionally, they recommend implementing network-based mitigations including proper network infrastructure controls, firewalls, and blocking unauthorized traffic. Users should also run all software with minimal privileges and implement the principle of least privilege (CISA Advisory).